I'm just gonna show you some simple way to help out your gun's life and it's performance. If you are new to airsoft this will be great for you but if you're not, you probably don't need to read this. And sorry if there is an excessive amount of reading, I just had a lot to say. Haha
Step 1: A Clean Barrel
A clean barrel is a happy one, and will make significant improvements when shooting(for most guns). This can be done on any type of airsoft gun(pistol, rifle, cheapo, expensive). Most of the guns you buy come with a rod that is used to clear jams and clean the barrel these actually work quite well if you use them right.
Put a little bit of cloth in the end that's got the little slit in it and put some lubricant on the cloth. Then put it in the barrel of your gun, slide it in there a few times then remove. I suggest doing this before and after using it.
Step 2: Batteries
There is a LOT of of info on batteries that is good to know but I know none of you want to sit there and read a freakin book on batteries. So I'll try to summarize.
mAh- this is the capacity of your battery. The higher this is the better. Most are around 1100 to1600. these are great because the bigger the number the longer each charge will last. If your gun came with some 800 mAh battery, I suggest getting one that's higher. I had this and I upgrade to a 1600mAh battery. It won't hurt your gun though if you're worried about that. It will simply last longer. And will need more time to charge. WELL WORTH IT.
There are three types of airsoft batteries-
NiMH-the most common and the most reliable
NICD-old and not used much. Develop a 'memory' of charge times. These things are weird.
Lipo- really weird to use and need special chargers. Very good for rate of fire and lifespan as far as I know... If they are used properly.
Conclusion-I know I didn't cover much but I suggest getting a smart charger for NiMH and NICD. They are like $25 online, and definitely worth it, I have one I've used for a while and it is great. All I use are NiMH batteries because they are just great overall and spit out the ROF I like from my gun. As long as it's like a 9.6V or so.
Tell me if you would like to know more, I'll be glad to tell you a lot more if you need.
Step 3: Gearbox
Your gearbox and what's in it will wear down and get dirty over time, but if you have a metal gearbox you really won't have to worry about it for a while, as long as you don't put your gun through some intense use and weather and such. Either take it somewhere and get help when you need it, or try and DIY. It is good to know how your gun works and how to clean it internally, so if you are comfortable with it, you should try to get into it and figure it out. The difficulty of it depends on the type of gun, spring guns are usually easier than most others.
Step 4: BBs
Use good quality BBs all the time. If you don't regularly get airsoft supplies online then go to Walmart and get the Black Ops brand BBs they are really good and always seem to work great in high end guns, as well as all others. I always get the 10000 BB jar of them. They are .2g so they are great for overall use in guns and grenades or anything else. I don't suggest Crosman BBs though, I used to always find deformed ones in them and seams and stuff.
Step 5: Problems/questions
Tell me if you have any problems with your airsoft gun and I will do my best to help you fix it. As well as any question your got on what I have put on here, I'll always answer. ;)