I think I'm not allowed to directly link to Patreon because of their ToS, but if you put "perverteer" after "patreon.com/" you should land where you want to go. ;)
Viewing post in Paid version cancelled due to itch.io policy changes comments
patreon's tos or itch's tos?
because, well, look at your itch settings, misc, connected accounts...
Linking to your patreon is not a problem. Do it on your profile, on your game, wherever you want.
But there might be problems in some cases for the content offered. Some dev claimed that they cannot offer the same version that is beyond a patreon paywall elsewhere. (Or was it patched/full versions? Can't remember exactly what was the problem. Point is, itch even lets you integrate patreon, whyever would anyone think that linking to patreon was forbidden.)