Like any other social platform, staying active is key. The more active you are and the more you invest in the Depop community, the more the community will invest in you.
1. Stagger your posts. Don't upload everything you're selling at once. Even if you only have a couple of items to sell, it drastically shortens your visibility in followers' feeds. Instead of posting 10 items in one day, post two items a day for five days. That way, your items are consistently popping up in your followers' feeds, which will result in more likes and follows. Likes and follows = sales!
2. Follow other users, like posts, comment on listings, and make connections with other users.