After a meal, walk for a few minutes. Treat it as the last step of eating, not a separate task.
It can be short. Around the block. To the corner and back. The length matters less than going.
Keep the pace easy. This is a stroll, not a session. You should be able to talk the whole way.
Pin it to the meal you most reliably eat in the same place, often dinner. One consistent walk beats three scattered ones.
If walking out is not possible, move around indoors for the same few minutes. The habit is moving after eating, however you manage it.
Done daily, the after-meal walk becomes automatic. You finish the plate, you put on shoes, you go.