Jeff decides to choose Diana, and specifically hiding in her shorts. So, Jeff starts off by running over to her, and attempting to climb her leg. Diana immediately feels him, however, so he has to drop down into her socks to avoid being seen; (This is going to be harder than I thought.)
Trying again, he instead jumps out. He starts thinking; If he can get high enough, he can jump onto her shirt and climb down. From his current angle, he's unable to see it, so he cannot verify that she's wearing one, but she wouldn't go out of her room without one.
Alternatively, he can continue attempting to climb up her leg, however he's seen that she will check quickly. He'll need speed for that option.
He continues thinking; A third option he could do is to swing off a loose string or something. While thinking however, he feels that it would be in his best interest to make sure she can't walk away, so he jumps into her socks.
Pushing aside the other two options, however, Jeff decides to try again on climbing her leg. First he gets out of her socks, before trying to decide the best way to do so.
Jeff attempts to jump as high as he can, before latching on and climbing fast. Diana, luckily, seems preoccupied with something else, and doesn't catch him. Around the time he reaches her knees, she starts walking to a nearby chair to sit down. Jeff has to hold on tighter from this point on, as he'll have to go on the bottom of her leg.
After another minute of crawling, Jeff makes it to the seat, where he relaxes for a moment. (Phew... I made it.) Without waiting for too long, however, he crawls into her shorts, and into pitch darkness. From here, he sits and adjusts to the darkness...