Not sure if garland is the right word, perhaps hanging is better. In any case this is extremely simple to do and we like it because we like to reuse our decorations from year to year and sometimes it rains. One solution we have for that is laminating pictures but hanging things often get a little worse for wear.
However, felt holds up fairly well in inclement weather and assuming your sukkah is shady enough, the colors of the felt pieces should stay pretty consistent.
This project is a basic cutting one of shapes of fruits and flowers. However, you could equally do stuffed fruit, decorate with beads/glitter/glue or whatever is of interest.