Place a plastic tarp on the ground outside your home, and place the suit on the tarp. Unbutton the suit, and open it so the inside is revealed. Shake the can of pyrethrin-based aerosol for 10 seconds to mix the contents, and then spray the inside of the suit. Then raise each sleeve and spray into it, and spray into any inside or outside pockets.
Turn over the suit, and spray it again. Then hold the plastic suit bag with the open end up, and spray into the bag.
Arrange the suit on a clothes hanger, and place the suit into the bag. Wind the end of the bag around the hook of the hanger, and tape the bag to it with strips of masking tape.
Hang the suit outdoors in a shaded area. Let the bag stay undisturbed for two days.
Remove the tape from the bag, pull out the suit and shake it off. Tie the bag closed with a knot and dispose of it, along with the tarp.
Upend the suit to remove flea debris and contaminants from inside the pockets, and brush off the inside and outside. Let the suit air out for a few hours before bringing it back into the house.