I got in trouble the first time I went out on a mission. It was just myself and an agent named [name deleted]. As the two of us made dead drops, staked out enemy agents, and stopped for a quick shopping trip (I had a coupon for pickles!), I'd tweet our precise location. (I did this so my mother would know that her favorite child was safe.)

But when [name deleted] found out what I was doing, she was Not amused. She took away my iPhone, broke my Twitter account, and confiscated my pickle jar.

Luckily, I had another coupon!

Anyway, my theory now is that spies should be like hikers. That's because when hikers go into the wilderness, their goal is to LEAVE No TRACE that they were there. Nothing but boot prints-and maybe some buried poop. As a spy, you want to follow that example! (Except for the part about the poop.)

In addition to leaving no trace, remember that escaping the scene of your espionage doesn't just mean that you get away today. It also means that you don't get caught tomorrow or the next day either.

So develop your powers of observation and cunning! Let's say that you've been tipped off about a top secret item that's in a room. Don't just go waltzing in to take it! As you approach the room's door, carefully look at the handle before opening it. Why? It's possible that someone has sprinkled a small amount of baby powder on the door handle to see if any intruders tried to enter. (I do this all the time at my house.)

*The KGB invented a "spy dust" that could be revealed using infrared lights. It was sprinkled on the doorknobs to important rooms. Then guards or officers would shine infrared lights on people's hands to see if anyone had been sneaking around.

It's also common for paranoid people (like me!) to place a small piece of clear tape on the door and frame. That way, if an agent returns to a room and the door tape is broken, she knows someone has been in there!

Solution: If you use the door handle, either avoid touching the powder or sprinkle new powder on it as you exit. As for the tape, note exactly where it is. Open the door. Then when you leave the room, do your best to replace the tape with a new piece.

Now you can enter the room safely, especially if the door is unlocked. But when you push the handle down or turn the knob, KEEP it pushed down or turned until you're through the door. Then gently close it and slowly let the handle of the knob latch. Nice and quiet!

If the door is locked, just use a key. No key? Pick the lock, already! (You'll find lock-picking instructions on p. 783 of this book.) Right, so now you're walking in, and you feel the small rug in front of the door give way slightly beneath your feet. Aha!

*Note*Instead of using tape, people have been known to wet a long hair and stick it to the door frame. I've always found this disgusting! So if you see a hairy door, I recommend you leave.

Rolling up strips of modeling clay and putting them under a rug is yet another way of seeing if an intruder has come into a room. If you return and find that the strips of clay have been squished, it's a giveaway!

Solution: When you leave, carefully lift the rug, reroll any clay strips you might have squished, and step around the rug on your way out.

Finally you approach the desk. You can see that what you're looking for is underneath a tray of marbles. Why marbles? Because whoever set up the tray took a digital photo of exactly where the marbles are!

Solution: Take a picture of the marbles yourself. After getting what you came for, rearrange the marbles according to the picture.