Great to have you back in the fandom ! I think a good way to get more into it is to look at art, and listen to music (pony of course) Thats how I got really into it. Also just be a brony online in general. That will also make you be more into it since you will become more of a brony as others look at you that way. That is actually the most important. Another thing that is causing me to be super interested right now is that I have an art commission from auhrelleah coming up, so I am really excited about this as well.
These are the reasons I am SUPER into it right now...
Also buy some Pony merchandise xD I haven't done this yet but I plan to soon.