Nothing beats a decent belt.
Even without suspenders.
Add a small backpack if you want to carry stuff like water and spare eyepro or bits and bobs with you.
As for camos pick something that blends in in your field, doesn't have to be fancy unless you're going for a specific look.
I currently run just a belt and a small pack for hydration, no extra mags, just a 1500/2300bb drum depending on the gun.
For tournaments I just switch the pack for a larger one if needed.
When I play with midcaps I swap the belt for a Helikon TMR or a TT Mini Mav, they're really low profile and light, I don't like having too much unnecessary stuff on me. You can check my kits in the loadout thread.
Remember though, there are only TWO things that you must NOT cheap out on:
Eyepro and boots.
First for obvious reasons, you only got one pair of eyes and they're quite rare to find spares for, and the second will make your experience much better, because going home with sore feet every time isn't exactly fun lol.