>>71271
It's really easy. Not much willpower needed, just get rid of all your browsers but Firefox, and get Leechblock for Firefox.
Remember though, you have to go to advanced options to you can keep yourself from reverting the site blocks during times in which they are blocked (but be careful with this because if you fuck up you can permanently lock yourself out of being able to change the settings).

Also, do not block one site at a time.
Also, use the etc/hosts file to lock Google into safesearch (so no Google images (I mean you can still fap to bikini pictures, but that's about the worst you can do (and even this you can block if you really figure out how to use leechblock (just do *google.com*+*bikini* (and variants of that (such as typos of "bikini") if you really wanna go deep))))).

how to lock safesearch:
https://support.google.com/websearch/answer/186669?hl=en