If you're starting leatherwork, this is a tight looking little project. Keep it up, and always ask guys like James Rogers, Sligo Bill and the other folks you see posting work.
When you sand the edge, try this;
Round the corners and finish sanding with fine paper.
Get a piece of canvas and wrap it around your four fingers, or an old cloth glove
wet the edges and rub in some beeswax or parrafin or a mixture of both. Don't take any prisoners
With the glove or canvas, rub the snot out of the edges so the heat of your friction melts the wax into the edges. Brisk and rapid swipes until you get the shine.
Keep up the good work.