If you could be patient enough not wanting to purchase an already ranked up account that meets your requirements, then I will advise.

Keep making good quality posts that inform and cryto-educate others and even posts that might be of value added interest in other areas of life affairs, and just like magnet to an iron you will attract merits which is one of the requirements for ranking up.

Your efforts and determination determines your level of growing speed in the forum.

Using myself as an example. I used just 2months or 3 approximately to rank up to member rank, now am eligible to wear a signature.
For some it didn't take that long as it did for me, that's where efforts differs.  Yours could be weeks possibly.