double up with (someone)

1. To come together as a pair with someone else. Have the students double up with a buddy on the field trip. We recommend that you double up with someone during the tour to make sure that no one gets separated. I usually double up with Kate when we have to do experiments in the chem lab.

2. To form two people into a pair. In this usage, a noun or pronoun can be used between "double" and "up." I'm doubling each person up with the student next to you. Please stay together the whole time we're in the museum. I know it's your first day on the job, rookie, so I'm going to double you up with an experienced officer. No, you can't double up Rich with Ben—those two can't stand each other.