The tape trick works pretty well as Robin mentioned.
The PE Cut Off Set by Small Shop is also an excellent way to cut off small PE while keeping them pinned safely in place.
I normally reach for my Small Shop cut off set now days instead of the old tape & cut on glass routine. The Acrylic cut sheets are hard enough to cut PE but give just a hair so the knife blade stays sharp longer.
For placing small PE, I use a “Dual-Ended Dotting Pen Rhinestone Picker Wax Pencil Manicure Nail Art Tool” - the wax end picks up the PE with ease and allows placing on the mini dot of CA glue.
The rhinestone tool is easy to find ebay Amazon etc and cheap.
The the CA sets, a bit of debonder on a paint brush to remove any extra CA that squeezed out or is exposed on the surface. I like the Black CA glue cause it’s easy to see. Plus the rubber in the black CA makes a better bond that resists shearing better than other CA glues.
There also a lot of other ways but that’s what I use and do for cutting & Attaching small PE parts.