Call of Duty 4: Multiplayer Guide (Introduction)

I've been playing Call Of Duty 4 Multiplayer a lot (primarily because MW2 multiplayer won't get past 'fetching playlists') and I believe I have become savvy enough to post a guide on how to survive a COD4 Multiplayer match.

These guides will involve:
- General Tips
- Etiquette
- Communication
- Custom Classes (and how to make them properly)
- Perks and Weapons (kind of adds on the end of Custom Classes)
- Maps (and strategies to go with them)
- How to make the most of your class
- Surviving 'Hardcore mode'
- Surviving 'Old School mode'
- Combat Tips
- Sniping 101
- Stealth 101
...And probably a lot more.
(These sections will appear in no particular order.)

I'll spread all these out over a series of Guides, each one specialising in a certain area.

So, stay tuned for the fist one. Shouldn't be far away.