My main suggestion is to start, and to start earlier rather than later. If you have an email account you don't like, every time you express that it's associated with you means you'll have to make one more update in order to completely switch.

I decided to switch around Black Friday when there was a discount for a paid subscription, and then to try to avoid using my old email account unless I saw a website reference it (like if I had to log in or specifically check for an email).

I feel a lot more comfortable using email than I used to (although I still try to avoid using it), so switching has improved my quality of life overall.