Always put a stitch marker under the top loops of the first stitch of your current round. Future you will be oh-so-grateful for a number of reasons:

1. You’ll catch mistakes early on. Every time you finish a round, count the number of stitches in the round and make sure it matches the pattern. Use the stitch marker as the starting point for the count.
2. When you lose count of your stitches, just start counting from the stitch marker to find your place again.
3. When you inevitably make a mistake, undo your stitches up to the stitch marked by the stitch marker. (Otherwise, you’ll have to undo everything every time you make a mistake. And trust me, that’s no fun.)

So do future you a huge favor, and learn how to use stitch markers to properly keep track of your stitches.