Thermal drawers (top - maybe two to change in case you sweat and you might get away with one pair of bottoms) with sweatpants for ease of movement and a bit of warmth. A long sleeve T-shirt or two to either swap as mid-layer(s) and a hooded sweatshirt as an "inner outer" layer. The last layer can be considered the field coveralls. You can tuck in the hood if it makes you too warm. You risk getting the hood stuck or hung up on something if you leave it out.
A neutral color bandanna can cover your head for warmth and sweat management, while another can be worn "bandit" style to cover your throat area, warmth,minimal protection, but better than taking a frozen ball directly into your throat. If you can't find bandannas, cut up a black, tan or brown T-shirt. No bright, vivid colors, otherwise you present a good target.
For the first game you might want to use the entire setup and adjust layers in between games as you warm up. The whole idea of this is adding "fluff" bulk without actual bulk.
Bring a can of shaving cream for some fog-resistance for your goggles. Smear, rinse and shake dry for for some temporary fog relief, reapply after each game, or until you get your breathing under control.
Any protective gear you can scrounge up, such as shin guards, knee pads, elbow pads can increase your intensity of play because you can dive faster, crawl harder and make yourself pretty damn hard to hit. I would suggest getting your own personal "jock gear", though.
You may want to build your own ghillie suit if you can wear your own gear to the field. This might be a bit on the warm side, but the terror you project as you pop up out of nowhere spraying paint might be worth the effort.
You can make some ghetto armor using pieces of bike tires or garbage cans. I'd use the tires as outside cover and keep the plastic garbage bits hidden from view. If you are hard core enough for this type of approach, you can paint a skull face on your goggles if you get your own gear. Cover it with the mosquito netting you can find in most modestly-equipped sporting goods stores. It makes a nice impact when you pull down the net and charge a bunker or entrenched opponent.