Do what your doing now! (Not making threads like this all the time) Just post around and share ideas and/or anything else you think should change and hear other people's opinions. Ask for help with something or a question you have been pondering. Pretty much just chill and be yourself on the forums and make yourself known. To meet more people comment in all sections, some people only hang out in one or two forums. That's pretty much how.
You just gotta be active and be frequent in discussion! I don't know what exactly was it that made me meet a lot of people here, but a big factor was "making myself known". You can also meet people by playing various games. Back in the day, Freerider2 was still kicking, so I made some maps on the comments, while people tried them out and commented on my profile how well (or terrible) I did. There was also an unofficial flash game tournament in either late 2009 or early 2010 that expanded how you interacted with people in games. It was a lot of fun, and it would be nice to bring that back again.
Anyway, there are plenty of ways you can meet people. You just gotta do it frequently enough that you get noticed. If you have an awesome opinion on a topic, be sure to speak your mind! Someone may agree with you or praise you on your opinion and comment on your profile.
Honestly, the biggest factor that influences meeting people on AG is activity. Lots of that can go a long way.
Maybe when you have signed up you could have introduced yourself at the newcomers forum and you can meet new people there by checking the forums. If you post a lot you can be noticed too.