I have a straight line capper made of plastic that I got cheep at a Wal Mart end of season sale. It works ... ok for the most part. It will sometimes drop a top hat for no reason it seems.
When I used to use them I just carried them loose in my blaze orange vest pocket. I couldn't hunt without the vest here, so I always knew I had them with me. They're so easy to handle I never thought a capper was needed.
You could also get a cap pouch. Regimental Quartermaster or Dixie has them. They're worn on your belt. Been using one for years. Hunting critters and yankees...
2nd corporal with ordnance
1st Texas Vol. Infy. E Co.