As u/protynie said, it can take months to retrain yourself to respond in different ways, and it's definitely harder for some people than it is for others. Here are some guidelines that have worked well for many women:
Stop all pressure-based masturbation and sex, even grinding hard in PiV. If you've tried before and it hasn't worked, you need to quit for at least 2 months before you start trying to learn new methods.
Schedule time that is all about you. A two-to-three-hour block once a week, three one-hour blocks on different days, or whatever works best for your schedule.
Most women who have done this agree that it really helps to have a good strong vibrator on hand. If you've never used a powerful vibrator, many women swear by the Hitachi Magic Wand, but there are other good choices. Be sure to have a small towel handy. If your vibrator is TOO strong, at least to start with, you can use it through the towel, folding it over if necessary.
Each time you do this, do everything you can to reduce your personal level of stress beforehand. Get a good night's sleep, exercise, meditate, get a massage, take a long bubble bath, drink a glass or two of a favorite wine, whatever works best for you.
Lock your door and turn off all alarms, phones, and extraneous devices. Dim the lights, put on some music you find sexy or romantic.
Put a towel on your bed, and have your favorite vibrator and toys and some warm oil on hand. Coconut oil is a favorite with many, but any vegetable or nut oil will do.
Get into bed and prop yourself up some pillows in a comfortable position.
Get yourself into a sexy frame of mind. Read erotica, watch your favorite porn, fantasize about your favorite hunk, reminisce about the best sex you've ever had - again, do whatever works best for you.
As you get yourself warmed up mentally, start massaging your breasts, abdomen, inner thighs, and vulva with some of the oil. Don't worry about getting aroused. Just do whatever kinds of touching, tapping, tugging, and rubbing feels good while you are fantasizing or whatever else you are doing mentally. Try NOT to be focused on arousal or orgasm. Just enjoy the sensations. Experiment widely with different areas, directions, speeds, and levels of pressure, but keep your fingers moving and don't press hard on your clit or vulva.
After 10 or 15 minutes, start using the vibrator on the outside of your vulva - on both sides; at the top near your pubic bone; and near the bottom, on or just under your vaginal entrance. Be gentle and try to discover which areas feel best and are most comfortable.
Keep exploring with the vibrator for at least 15-30 minutes. You may find that your preferences change over time as your labia and clitoris become more aroused and fill up with blood.
If you do get aroused, try to stay relaxed and don't get impatient and push for an orgasm. Having expectations and getting frustrated because an orgasm doesn't happen immediately on command is a very common problem. Don't set time limits and don't try to force anything to happen. Just be prepared to float in a sensual fog for as long as possible, enjoying the pleasant sensations.
The first few times you do this, your only goal is to get acquainted with the range of sensations that different kinds of touch and vibration can provide. Stay present, focus on sensations, and try not to think about what you're doing in an analytical way. "Spectatoring" - observing yourself as if from the outside - is a very common way to keep yourself from getting aroused enough to have an orgasm. If you catch yourself doing that, tell that critical observer to shut up and go away, and just relax and enjoy the process.
When you do find a rhythm and pattern of touch that lead to increasing arousal, keep doing that. Eventually, your brain and nervous system will connect the dots and you will have an orgasm. It may not be as strong as the ones you are used to. That's okay. This is a learning process and that's a start. Repeat often, and it will get stronger.
I posted a long list of links to other resources in response to a slightly different question last week, but they all have to do with helping women become orgasmic and learn to have better orgasms. Have a look. There are some terrific books and websites there!
Good luck!