Checking in regularly with your mates lets them know you’re there if they need you, and helps keep the conversation in play.
Once you’ve had a kōrero with them make sure you remember to check in again. Putting a reminder in your phone is a useful tip.
Take the lead on reaching out to them and suggest a catch up. This helps takes the pressure off them.
Let them know you’ve been thinking about them. You could say “I’ve been thinking about you and wanted to know how you’ve been going since we last chatted”.