Try and start and end your day at the same time each day.
Have a dedicated work area if you can.
Make sure you force yourself to leave the house. Sometimes (especially in the winter) I'd find myself realising I hadn't left the house in a couple of days. Taking a walk at lunch or driving into town after work are good ways to take a break.
Try and update either your team or someone you work with a lot on what you got done for the day. Either in a daily standup or send out an email at the end of the day.
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Good question!