If you're just beginning your 3D printing fabric journey, start here! This includes a 3mf with print settings for 5 different basic patterns. There is a square, circle, and hexagon pattern, as well as two versions of studs.

I have added some video links that will help explain the process, more in depth.

The flat designs are intended to be printed face down, so the bottom layer that prints first, is the top layer with either the textured finish, or from a variety of different PFLAT options - https://kaizen3dprints.com/collections/p-flat-plates

Fabric sample packs can be found here - https://kaizen3dprints.com/products/fabric-sample-pack

If downloading just the individual STL -

Add a pause command at the beginning of the second layer - Second layer print speed should be slow as well. Add fabric of your choice and tension with magnets Resume print - The filament will attach itself to the layer below, creating a fabric sandwich with layers 1 and 3, with the fabric in the middle. Remove from the build plate, and sew / attach / fidget with / create anything your heart desires. If you want to print more complicated things, check out my Thangs membership for additional projects.