TL;DRers have been warned:

I will also warn that I may digress as well. It's not wrong to disagree with David Copperfield, nor would I say it's wrong to agree either. Being surrounded by people who were proficient in only 1 or 2 disciplines, I've always thought being a polymath was impractical when I was younger, and I was convinced that the reason it even came up in my mind in the first place was because I'm indecisive (just like my difficulty with picking a favourite genre of music, favourite cuisine, etc). However, the more I thought about it, the more I romanticized with its concept. Now, I can proudly say it's my biggest endeavor, which I'm hoping all of you polymaths out there do as well; regardless of what other people think.

In an age where all trades and disciplines have evolved considerably, I believe mastery takes a lot more to achieve than it did maybe 600-300 years ago (Renaissance). With that said, my philosophy is that you should kill as many birds as you can with as little stones as possible. For an example, in my physical fitness outlet, I am a bodybuilder. Instead of running, I took advantage of the cardio aspect of bodybuilding and decided to learn something while doing cardio by taking up a martial arts class twice a week and dancing on the days I'm not getting my ass kicked. Get a job that will help you get better at something you intend on doing instead of maybe being a cashier at McDonalds (unless that's your thing). Instead of reading novels, read textbooks. Surround yourself with people that are proficient at disciplines you intend on improving on. Make a diary for the disciplines you wish to learn about, and keep track of each one. Set short term and long term goals. Determine how much time you will spend on each discipline in an average week. Determine which disciplines will need certificates, degrees, and which ones won't. Rate each discipline on a scale of 1 - 10 for how good you are currently at it and how good you would like to be at it before you die. I'd recommend only letting 1 - 3 disciplines go past 8 (main disciplines). For me, I chose Culinary Arts, Music, and Programming. It's also okay to have a few disciplines that you are good at because of previous learning, but rarely spend time on - it could just be something you have hidden behind your sleeves. Keep an eye on the ones that disciplines that matter the most to you. Many sacrifices are to be made. It's a busy life, and I've learned to accept that. I've gotten used to staying in on Friday and Saturday nights just learning shit, while other people are out partying. It does wonders for your self-esteem, and a lot of other things. So to my fellow Polymaths of Reddit, let the world know your name and why you're here. Let us represent a master race one by one. Don't be ashamed to tell yourself once in a while "I'm good at a lot of shit"