Each step in the 'Ible will be on each different theme. So I will put in a picture, and get down to business.
Disclaimer: Please always wear eye protection as airsoft can be dangerous. Please wear the appropriate clothing, don't play on land that you are not allowed on, check your local laws to see if playing in certain areas in alright etc. FOLLOW THE RULES
I do not claim ownership of all these pictures
Step 1: Equipment and Different Roles.
Gear for Roles (May vary depending on playing location)
Heavy Infantry: High RPM AEG Rifle(SAW), Secondary AEG, Extra BB's, basically quite a bit of extra equipment which might include grenades, smoke bombs, and others.
Sniper: High FPS Sniper rifle (Depending on field of CQB. I prefer Bolt Action Spring guns, they are usually quieter and reliable, plus who doesn't love bolt action?!) either a small AEG (ex: Mac 11) or semi-full auto pistol. May want a spotter. Maybe a sniper gillie suit if you have the money.
Assault (Your basic role): AEG Rifle(Basically anything) (Yet again, high FPS[350-up] for bigger fields, lower FPS[Under 300]), backup pistol, maybe extra ammo.
Scout: Scouts need to be able to blend in with their surroundings and move quickly and silently. They will want a mid-sized AEG(M4, P90, alot of options), and a backup pistol. May want a gillie jacket to quickly blend in.
Special Ops: Your backbone, need to be able to take on any role. For their basic role they will want a nice AEG(Yet again, M4!) and a good secondary. Depending on different missions they need to do, they will need weapons to fit.
Medic: Real medic and just the role, should have an emergency kit and 'Dead Rags'. Pretty much just needs an automatic rifle to be able to defend themselves as they try and get to the wounded. May want and armband for people to identify.
Step 2: Fields
If you are playing in a big area where you won't be up-close with the enemy, you are going to want guns over 360 FPS. If you can, you may want to make forts, which I will cover later.
If you are playing CQB (Close Quarter Battle) you want lower FPS gun, anywhere from 200 to 300 FPS.
Step 3: Bunkers and Forts and Fox Holes, Oh My!
Fox holes are basically for Snipers. What you will do is dig a hole maybe 3 feet deep by 3 feet wide and depending on how tall you are, 5 feet in. You will mostly want to build it into a hill. What you are doing is making a small 'cave' for you to hide in. Cover it up with camouflage and you are good!
Bunkers: For these you need a shovel and some plywood. They are very labor intensive and depend on how deep you can dig and how long you can get it. There are many different kinds, but im going to focus on covered and trench designs. For the trench, you just need to dig maybe 4 to 6' down and however long you want them. You know, a trench. For the covered, you are going to dig a area maybe like a big square that you will build walls out of plywood, sink them along the edges and make a roof, so you have a sort of a sunken fort.
Forts: They can be anything for up in a tree to down on the ground, also tree stands! :) They can be as simple as placing plywood in a square to as complex as making an entire shed or small 'cabin'. The easiest way is the get plywood and some posts and sink your posts into the ground and the kind of formation you want your fort, then use the plywood to make walls by nailing them to the posts, please dont nail them to trees, it hurts them!
Step 4: Go Play!
For those who did enjoy it, i'm glad, and if you have any questions feel free to ask. :)
Have fun and don't forget to wear safety gear!