Walk, don't run. Running (when your soldier's path turns red) can alert nearby guards and ruin your stealth approach. Instead, stick to walking (the blue path).
Disable alarms. These will turn off nearby security cameras, and stop enemies from alerting other bad guys if you get spotted. Also, dispose of bodies if a guard is likely to stumble upon them.
Use grenades and claymores carefully. You have to pay for new ones with tokens, which could be better spent on armour upgrades and a third perk slot.
Before the start of each mission, you'll have the opportunity to change the loadout for each soldier. Try and condition them based around your style of play. If you prefer the sneaky route, use the Stealth class, suppressing enemies with silenced pistols and sniper rifles. If you're more of the kick through doors type, the Assault class is ideal.
Don't be afraid to mix and match loadout types through the Custom option. Here, you'll be able to change weapons for each of your soldiers. Try to find a balance with your team, where one has good up-front weapons like a pistol and assault rifle, and another is at the ready with long-range weaponry. Play with different loadouts.
Over the course of the game, you'll gain access to new weapons, purchasing them before each mission or via care packages. Try to get as many as you can, as you'll have more options to choose from. The basic guns work fine, but you'll want to upgrade later.
When you see red lights flashing in the overhead tactical view, that's an alarm system, just waiting to catch anyone on the prowl. If you see one of these, find the control box that shuts them off. First take out the guards in the area. From there, deactivate the alarm and move your team forward.
You can earn a good amount of money in each mission, but it never hurts to add a little more. You can do this by sending Challenges to friends, where you can see how they fare on certain mission objectives compared to your best times. This is a great way to socially interact with others in the game, especially since there's no multiplayer component.
Strike Team has a little something extra for veteran Call of Duty fans. If you have access to a Call of Duty account, you can sign in for exclusive in-game bonuses, such as weapons and coins.
Keep an eye out for Intel. These little slips of paper can be found strewn throughout each level, with 48 to find in all. The more you locate, the closer you get to unlocking one of the game's Achievements. Just remember that you have to complete the mission for your progress - and Intel pick-ups - to be recorded.
