This will work for a single chip:

1) Take a used 000 (5" x 8") bubble envelope
2) Cut a 2" strip off the short end of the envelope, strip will be 2" x 5"
3) Put the chip in the strip and tape close
4) Put the strip in a regular business sized envelope
5) Seal envelope and then use packing tape to seal again for extra protection
6) Envelope should be under 1 ounce, so put on 45¢ postage and (if you want to) add another 20¢ postage for the rigid object. This is important ... put on the postage yourself, do not bring to the post office to have them do it, they will want to charge you a lot more if they do it.
7) Mail the envelope by putting it in a mailbox yourself.

This has always worked, never had one returned. For more than once chip, adjust accordingly, but keep the size to what will fit in a single layer of chips in a regular business envelope. If you are sending a lot of chips, use a large bubble mailer, single layer of chips and put in a large (like 9" x 12") envelope. If the bubble mailer is inside a regular envelope, the post office will just charge the large envelope rate rather than the more expensive package rate. When you get to about 13 ounces, a flat rate priority envelope or box is the lease expensive way to go.