How to make a server?

Download steamcmd download Addons, darkrp mode, darkrp modification and watch tutorials)

You can make a local one with Steam CMD or you can buy a host for a dedicated one. You can also run one from your computer but I wouldn't recommend it myself as it's very risky.

Well its a long process but i would start by making a document for all of your economy ie

How much printers make a minute
how much weed makes a minute etc etc

a perfectly balenced economy is a great start to a gmod server