There are two types of PE parts
1/ with black backing sheet - better since there is no trimming needed to get final part.
2/ attached to tree - trimming of attachment needed. This trimming process can result in a damaged part or even the loss of the part.

Taking parts off black backing sheet
1a. Use edge of #11 x-acto knife and pry off
-careful not to fling parts away
-small parts can be cut in a small clear bag so if the part flies away it will be in the bag somewhere
1b dip in lacquer thinner until part comes off (never tried this)

Taking parts off sprue
2a use small sharp scissors (yes it probably will dull the scissors quickly but i have found this to be the quickest and cleanest method) (found that the scissors I used (cuticle cutting scissors) to be very good even in tight parts of the tree)
2b x-acto knife on cutting board. One way to get around this is to apply masking tape to the back before cutting. Try using a low tack masking take to prevent goo getting on to the back of your PE part. If your PE part is stick do not force it or you may accidentally bend it.(thanks to Paul for the suggestion)

Trimming of tree parts
For quick trimming of larger tree parts the same scissors were used. For the finer stuff nail files seemed too stiff and may bend deform the pe part. Used emery boards, fine files or medium grit sandpaper. Sanding parallel to the surface of the part and never perpendicular to it since it may bend/ deform the part.

Application
1/ superglue (CA type glues), clear enamel or white glue - use small amount and sand both surfaces (400-600 grit) so the glue has something to bite into. Clear enamel is another option that isn't as potentially harmful as the CA glue and would be stronger than white glue. (thanks to Paul again for the enamel tip) The white glue will be the weakest bond but there are no worries that the glue may harm painted surfaces. (See figure 1)

Drill hole in the middle where the new photo etched item is to go. (In this case we are replacing a dzusses 1/4 turn fastener). Next sand off the kit part. Paint the kit part and when this is dry glue the new part on

2/ with tape and alignment method (See Figure 2)

After following the first two steps as above this is a method of lining up the parts correctly. Place the PE part onto the model in the desired location. Place a piece of tape over all or part of the PE part. Lift the tape and PE part slightly so that some of the tape is still on the model and all of the PE is off the model. Apply a small amount of glue to either the model or PE part. Not too much or it will squeeze out when you put the part down.

3/ drill hole from behind and use wire (tricky sometimes) (See figure 3)

This method can be used every so often. After following the first two steps you thread a wire through the hole. Add a touch of glue to the tip then put the PE part on this. Pull the wire down through the model and the PE part and glue will be left on the model. This method is mainly used for CA glues. The tape method has problems with the glue getting all over the tape then onto the model

4/ Toothpick and hemostats
5/ For very small parts (bolt heads) slightly wet the tip of an x-acto knife and this will be enough to pick the part up

Painting
Lightly sand pe parts with 400-600 grit sandpaper. This will provide a tooth for the paint to grab on to

Bending pe parts
1/ Long straight hemostat or vice - be careful that teeth do not bend or put marks in part. Use metal ruler or other item to bend part. A small vice will also do. Do not use fingers as this will produce an uneven bend.