The link from cissrawk should give you everything you need. However I don't think you should be focusing on activity. Presumably you want to increase your activity in order to rank up. You will discover that there are both activity and merit requirements for each rank, the pertinent part of cissrawk's link being the table below.
Increasing your activity is easy; just make some posts. Increasing your
merit is somewhat more of a challenge, and in practice, for the vast majority of people (myself included), it is merit that is the gate to the next rank. In theory, if you make good, constructive posts that are valuable contributions to the thread, people will award you merit. There are numerous threads that advise on how to get merit, but they basically all paraphrase the above.
In addition to activity, everyone now has a merit score, and you need both a certain activity level and a certain merit score in order to reach higher member ranks. The required scores are:
| Rank | Required activity | Required merit |
| Brand new | 0 | 0 |
| Newbie | 1 | 0 |
| Jr Member | 30 | 1 |
| Member | 60 | 10 |
| Full Member | 120 | 100 |
| Sr. Member | 240 | 250 |
| Hero Member | 480 | 500 |
| Legendary | Random in the range 775-1030 | 1000 |
You get merit points when someone sends you some for one of your posts. Additionally, when someone sends you merit points,
half of those points can be sent by you to other people.
