Try and retrace your steps. Think back to where and when you saw the ticket last and concentrate on that area. Consult a diary if you have one to make sure you revisit everywhere you have been lately. Make sure that you look through any waste baskets in the area you remember seeing your ticket. Check your all pockets and any bags that you have used recently.
Look through all the places at home and work in which you keep documentation. Be thorough as you may have simply misfiled your plane ticket, and it may turn up somewhere that you wouldn't expect to see it. Look through newspapers and magazines if they are lying about the house.
Check with anybody that lives with you if they have seen the ticket or recall where you had placed it. If you have children, check their bedrooms, school bags and play areas as they may have innocently picked it up as paper to play with.
Check online and see if the airline has sent you an e-ticket as well as a paper ticket. This may serve as a replacement. If you have lost the e-ticket, check through your deleted items and see if you can recover the original email.
Contact the airline and explain the situation if you are unable to find the ticket. The airline should issue a replacement, although policies vary among airlines. Some will charge a small fee, while others will re-issue it at the original price.
