PEI Ultem is easily cut to size by scoring with a hobby knife. Laminate your sheet of PEI using 3M 468MP Adhesive Transfer Tape that came with the PEI sheet to a glass/mirror print bed, keeping in mind that 3M 468MP is a very sticky tape that is prone to clumping. Parts should come free from the surface with almost no issue at all. PLA does not require heat, but turning the heated bed up to 45C helps. After the print is done, just let the plate cool down and then gently you can just "pop" the model off the plate. Before each print, wipe your PEI Ultem surface down with 70-91% Isopropyl alcohol, to ensure that you wipe away any grease or other residues that may have accumulated on the surface. This will help increase your surface adhesion greatly. Use isopropyl alcohol, methyl alcohol, or soap to clean your PEI after use. In other words, PEI can be cleaned through the use of Isopropyl Alcohol, which will theoretically help adhesion should you lose it. This is sheet are made of 100% genuine PEI Ultem material. You can clean them with acetone if you want