any suggestions on how i can get my server bigger and make more people join?

You want to make your server stand out amongst all the others. Make sure your server isnt just the standard sort of server. Get creative. Maybe hire someone to make custom addons for you, that usually attracts people.

More information on your server? like, what premium content you got, or rather what custom content do you offer that no one else does?

I think it would be nice to you to make some server very different from the normal RP like they are doing on Brazilian servers

Make sure it has more players, and have things that just make it better than other servers. The way I managed to get players to join my sandbox server was just to play with my friends. Since it had players, more players joined

I would say just invite your friends and market your self well it also helps if you have things like Free VIP Need staff and stuff along those lines

Keep it running. If you go onto other servers adverting how your server is new it will just prove your are desperate and if your desperate you're probably going to have a vulnerable server which is not ok.

Make sure not to have like 100 things you can buy with real money, have only donator and vip and it should unlock only a few jobs that are upgrades to free jobs.
Just make sure you don't have any cancerous SUPER EXTRA MEGA UBER VIP (NOSCOPER JOB 1 HIT KILL 9999999 RPM WEAPON AND CAN RDM)

You should hire people to make addons for you and have a name that stands out (Just steal popular servers name - who cares really.)

make posts on it in the gmod discussion or tell ur friends and tell them to share it