head in
1. To prepare to enter some place or thing. I'm going to head in now—it's gotten quite chilly out here. Lunch is almost over, so why don't we head in?
2. To start moving the front end or part of something into some thing or place. If you head in carefully, I don't think you'll hit the cars on either side of the parking space.
head in (to something)
to move into something head or front end first. Head into that parking space slowly. It is quite narrow. I turned the boat toward shore and headed in.