TL;DR: Never, ever skip basic personal hygiene. Focus on reducing Impossible Days before even worrying about Good Days, but know that Good Days will come. Conserve your energy. If you have unhealthy habits, don't worry about dropping them right away, but do take harm reduction steps (google "harm reduction your unhealthy habit]".
What they don't tell you is that depression is a terminal illness. You have to fight just as hard as someone else with a terminal illness. Yes, I'm glad I have MDD instead of cancer. I still have to use absolutely everything at my disposal to get through.
I can tell you right now, as a fact, that you will get better. I'm not going to pull punches. Some people will live with depression and other mental health conditions their entire lives. But I can tell you, as someone who has seen it all, that you can live a life worth living. You can become well enough that your bad days are infrequent and your impossible days are annual, not weekly.
Right now I'm on medical leave, so I'm in therapy with a Psychiatrist. This isn't the norm - usually you would see a psychiatrist regularly but infrequently in conjunction with regular and frequent sessions with a therapist; preferably a clinical PhD or an LCSW. I am in individual therapy for four hours per week and group therapy for an additional four hours. This may not be an option for you. If it is, use it immediately. Take a medical leave of absence from work, move in with an understanding family member, drop everything and learn how to live with your depression. Unfortunately, particularly if you are in the US or still in school, this probably isn't possible. Start with trying to see a therapist weekly and a psychiatrist monthly, and work backwards based on your insurance, transportation, job, etc.
You will have Good Days, Bad Days, and Impossible Days. Learn to distinguish. Your first goal is to have more BDs than IDs. This will take weeks. You will have a lot of BDs, but you will think they are GDs, and thus you will decide life is not worth living. This is the lie of depression. BDs are not GDs. They are just better than IDs. What I didn't understand when I started fighting my depression was that there was something better - that I could experience - than a BD. Your second goal is to reduce IDs to infrequency and irregularity. This will take months. Your third goal is to have some regular, predictable GDs in your schedule. This will take months. Your final goal is to have GDs more often than BDs. I cannot tell you how long this will take.
Coping is about conserving energy for the things that are important: maintaining the basics of maslow's hierarchy of needs and stress release or pleasure (depending on whether you are more anxious or more anhedonistic). I like to say that I have 10 fucks to distribute during the day. On an ID it can take 8-10 fucks just to get out of bed. On an BD it usually takes 4-8. On a GD it takes 1-4. As depressives, it will probably never be a freebie. It may never take less than 2. That's fine. Deal with the hand you have.
First things first are the non-negotiables. This follows the principle of no zero days. I'll get to that in a second.
I don't care what you do, or what kind of day it is, you do not skip your personal hygiene routine. Ever. I don't care how much you overslept, I don't care how late you are, you may not skip your personal hygiene routine. This is as important as any medication you take (don't skip those either). I'm not talking lotions and facial care and little beard trimmers. Take a shower, which includes washing your hair, body, and ass, brush your teeth, and put something down your gullet. Always. No exceptions.
Streamline this routine so that you have a normal version (1 Fuck) and an abbreviated version (half a Fuck). If you are using the abbreviated version more than half the time, that's your new normal and you need to abbreviate again. As long as you are showering, brushing your teeth, and eating something, I don't care what you are doing. Buy 2-in-1 conditioner. Buy that horse shampoo stuff that also washes your body. If you are female-presenting or female gendered, do what you can to get away with not shaving. It's a waste of energy right now. If you grow facial hair, find out whether it is less work to stay clean shaven or to keep a beard in check. Keep your goddamn beard in check. This is not an optional part of the routine. You may think this is unfair, but folks with periods have that to contend with, so it evens out. If you have both facial hair and a period, you are probably at some stage of a gender transition, and your daily routine is just going to take more time than someone who isn't. This sucks. I'm sorry.
Download a habit tracking app to your phone or make little boxes on a piece of paper and write down each step of your morning routine. Don't write down "do morning routine." Write down: wash body, wash hair, deal with facial hair, brush teeth, take medication, eat literally anything. I don't care if you are having an ID and you are going to stay in bed all day. Get up, do those things, and go right back to bed. I've done it. You'll do it. It is going to happen.
Now you have the hierarchy of needs problem. This means you will probably have to go to work or school or maintain a "good enough" relationship with the person that provides for you. Remember how I mentioned energy conservation? You need to find out how many GDs, BDs, and IDs you are currently having. You need to find out how many Fucks maintaining your basic needs requires, and accept that you will need that many fucks just to get by. That might mean you need a minimum of 13 Fucks to live and you only get 10. We'll talk about how to borrow Fucks on credit in a second. If you're an anxious type, you might be able to safely shave a Fuck off your work or school, but if you're anhedonistic type, you probably need to add one or two Fucks to whatever keeps you fed and sheltered (and hopefully insured). If you're both/atypical, you probably need to make sure your more/fewer Fucks ratio is keeping gainfully employed (or in school or in a relationship that supports you).
After that we have a pleasure or release need. If you don't do this you will succumb to depression. I'm sorry. So, you know how you have 10 Fucks a day? If it was a BD or ID, by the time you get done with work (or realistically sometime in the middle of your shift) you will have run out of Fucks. This means you need to regenerate Fucks. There are slower, sustainable ways of doing this and faster, more detrimental ways of doing this. Right now, take stock of your life and figure out what is helping you get by. Staying in bed? Alcohol? Weed? Something stronger? A dog? Video games? Those are all ways to regenerate or conserve Fucks (or just not use any by lying in bed).
Yes, you want to get to a place where personal relationships, pets, creative outlets, your hobbies, etc. are the source of Fuck regeneration and conservation. That might not be where you are.
If you are using a substance to regenerate or conserve Fucks, focus on harm reduction. Google it. This means not stopping what you are doing but trying to do it more safely. If you are smoking weed, see if you can switch to lower dose edibles (ie not harming your lungs). If you are drinking, I'm not asking you to stop drinking, I'm asking you to google alcohol harm reduction, pick one strategy, and implement it. If you binge eat, make sure you never have more than a single binge of what you tend to binge on in the house at the time, but always have a small amount, or you'll just go to the store and get it, and because you'll already be in binge mode, you'll probably get a shitload of it. (For example, always have a pint of ice cream, but never stockpile pints or buy half gallons. You will go to the store to get ice cream if you don't have it, so fucking have it, but make sure a pint doesn't become a quart.) If you are using other drugs, the good news is harm reduction is simpler (find a source of clean needles, make sure your acid is unlaced, whatever), but also, you might have a drug problem. You can't deal with that right now. Reduce harm first.
If you don't use drugs or alcohol, go to great lengths not to start, especially alcohol. Try not to know where to buy drugs. Swear off social drinking if you can; if it's already a part of your life, focus on keeping it social or harm reduction. If it's not, don't start. In some cases, particularly for anhedonistic depression, if you are in a legal state you may consider cannabis. There are serious pros and very serious cons to this. Cannabis can help you eat if you are a depression non-eater. If you are an anxious type, it might help you relax (or exaggerate the issue - everyone is different). It can reduce the number of Fucks required to participate in hour hobbies or relationships, thereby actually helping you regenerate Fucks. However, cannabis can deepen depression, cause anxiety, and decrease motivation. You may not under any circumstances begin a cannabis habit if you are under 21 - not because of the law, but because your brain is still developing. If you already are, again, focus on harm reduction, but don't start if you aren't.
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