Honestly its a tough thing to get a SG going and keep it active. Take it from someone who has led several. You pretty much can do it one of 2 ways.
1. Simply find a cool name and let anyone in, then try and find out if any of those people want to be a part of your leadership. Once you have a handful of people who are in your leadership positions, actually give them some control and give them the leeway to actually do things. This will give them incentive to help the SG along. You may get a lot of people in the SG but this type of SG will have a big drop out rate, so you will need to keep recruiting often.
2. Find a niche that you will enjoy and simply stick with it, find a theme and recruit like minded people. This will take potentially a lot longer, but youll find that the people you do get into it are more likely to stick with it.
Just my 2 inf 
Mains: Xero Curve, King Geo, Ahnix, Sphere of Light.
Globals: @XeroCurve, @ZeroCurve
Based on the content of your previous posts, I'd suggest that you wait another year before you attempt it. It's going to be hard to get anyone to join your SG if you have problems clearly presenting a case for why they should do so.
I want to start my own SG. It's for both non-RP'ers and casual RP'ers (not full time or main). Can anyone suggest tips on getting people to join? I don't see any high lvls that are not already in an SG.