onethreebravo
A little bit of silicone spray is good in the breech. I suggest using silicone grease on the inside with the gears and on the piston and cylinder.

Moe
I would just go to Airsplat.com and check out their maintenance page. They have a lot of useful information for those looking for it. just take the time to look. Here's the link to make it a little easier for you:

SuperM
You want to make sure that you only use 100% Silicone lube for your airsoft gun or you could damage the seals. Spray a 1 second burst up the mag well, and down the barrel end. Do this before you use the gun so that during use the lube will be distributed into the gun. Wipe off any excess so that it doesn't attract dirt. You can find this information and more on the following link: