Begin a journal or memory book if you are prone to physical phenomena.
Purchase an inexpensive camera. (For some reason they seem less capable of messing up a really cheap camera verses an expensive one.)
Make a self hypnosis tape to counteract the post hypnotic suggestions you have been given not to document or even remember the experience.
Anytime you experience anything that seems strange or unusual whether awake or asleep, record it in your journal along with the date and time. This includes any unusual dreams, coincidences or general feelings (physical).
Any time you find unusual makes on your body, photograph them. BE sure to take two photos. One photo should have a ruler next to the mark, preferably metric. If you don;t have one at the time, place a coin next to the mark. Coins are uniform in size.
Last but not least, if you have pets, be sure to note any unusual behavior they are exhibiting. Be on the alert for them oversleeping or seeming to be disorientated or drowsey. Note the time and date. This may coincide with your abduction as anxiety in the animal may. Fish seem prone to anxiety verses drowsiness.
If there is a pattern to your abduction, like noon every Thursday, either make certain you remain awake during this period or/and set up both a Video Camera and Tape Recorder during this period. This will allow you to rule out any outside interactions that may be interferring with your sleep or awareness. For example...a yard service working next that time on a regular schedule.