Keep to the regular ceremony of it.

Wear pants. Wear your whole work uniform, be that jeans and a button up or a suit.

Start at the same time every day. End at the same time.

I second that! Also, a dedicated space for working is ideal to keep the office dynamics. Most importantly, make sure to stay in touch with your team - it will help everyone to be aligned and on track.

take walks. You usually get walks in the office from meeting to meeting. This is small, but makes a huge difference to focus.