Wake Island is one of the four new maps featured in the Back to Karkand Expansion Pack. It's set in a horseshoe shaped island. This map was also featured in Battlefield 1943.
In Conquest, after the US team reaches the short from their base, they will have two HQs at both ends of the horseshoe patterned island. The RU team will not be able to reach the HQs.
Wake Island is a very open map and cover can be fairly scarce in some areas that aren't populated by buildings. The key to surviving is either staying on the outer-coast (inner-coast you'll be wide open to sniper shots), or finding some small cover like rocks/bushes if you insist on remaining topside.
Now if you're a sniper there's a relatively different approach which you would probably like to take, that is, remaining topside. However, as a sniper you can see virtually the entire island by hanging back towards the tip of the U (Remember Wake Island is U shape). In doing so the sniper will be relatively secure from an infantry ambush, but that doesn't mean that are invulnerable to sniper fire themselves.
So a quick recap; snipers hang back, infantry hug the outer-coast, that is... if you aren't to keen of seeing the respawn screen.