The simplest and quickest tree trims I have made … trace shape onto right side of fabric, sandwich three layers with fabric right side down, wadding (cotton is my favourite for this job) and the marked fabric right side up.
Stitch the layers together freehand with two or three rows of stitching along similar lines.
Add hanging thread and add to the tree.
Other shapes can be used the same way.
The stitching can be done by hand too.