The thing that helps more than anything else, for me at least, is to spend a lot of time in a community where everyone is invested in getting pronouns right -- because it can be hard if you're doing it all on your own, against the current, so to speak.
Luckily for me my workplace has gradually become such a place, where we used to never volunteer our preferred genders, to now where the norm is to introduce yourself with your name and pronouns if you're comfortable, put them on name-tags, and we all try to help each other remember people's pronouns.