Here are my tips:
1) Order custom forms online from USPS. com and keep them in your car, along with a few extra flat rate boxes and tape, if room allows. This way you can fill out the FROM section of the form if caught in a traffic jam. The extra boxes and tape will make you a hero with the post office customers.
2) Complete your customs form as you pack the box.
3) Order AS business cards and pass them out in line at the post office.
4) Wear your AS T-shirt or cap in line at the post office.
5) If you run across a new postal clerk, SMILE, slide the box across the counter with the custom form on top, and say "No, Yes but it's double bagged, No and No. I also do not want insurance". They are required to ask a series of questions "is the contents: fragile, liquid, perishable or potentially hazardous. Do you want to insure this package?". The clerk will then realize that you are a PRO and, hopefully, treat you accordingly.
6) If you are worried about the box being pilferred, write or put stickers on the outside. Colored stickers and bold writing gains lots of attention. This possibly keeps a dishonest person from absconding with the package. I suggest: "To my favorite God Son (insert name here) on his birthday", "To (insert name here) with love from his favorite elementary teacher". It doesn't matter to the soldier that you "streached the truth" on the outside, as long as he/she get the box. This actually protected a microwave I had mailed to Iraq. (If you also use the same colored stickers ever time, or the same box marking, your designated soider will recognize that the box is from you before reading the top.)
7) If you are mailing flat rate boxes you know the anticipate total, so if not paying with a credit card, use exact change. In many instances, citizens use the post office as a bank, using large bills. One dollar bills are usually, even a large amount of them, are totally appreciated by the clerks.
8) If there is an independent contractor, other than the UPSP (Mail and More, Parcel Plus, etc.) ask the owner/operator if they would be willing to mail your package without the mark-up, i.e. normal mail rate. Most will help you.
9) When the person at the back of the line at the post office makes a loud announcement, pointed directly at you, that "you #$#!* Ebay people need to get a real job and don't clog up my line at the Post Office", here are my tips:
A) Remain calm. We have a purpose here.....
B) Look for assistance in the line, especially someone wearing patriotic clothing, especially a man wearing a "Served In......" or "Son/Daughter Currently Serving .........." ball cap.
C) Ask that person to break from the line and to READ ALOUD for all to hear the address on your boxes.
D) If no one is available to assist you, do it yourself.
*** I have shamed multiple people from the local post office using the above mention actions.
Many thanks to those who suggested that the customs forms state that the package should be redirected to the unit's CO, XO or unit's clergy. I have come home twice and confronted "returned to sender" packages, although the form was clearly marked "give to any clergy". It sent me running to the www.dod.gov website to check the status of my contact.