Like most sports, bowling has a variety of paraphernalia designed to aid performance. Some really help and others are more for attitude than actual physical benefit. Don't treat those types lightly. They can be very valuable assets since you'll perform better physically when you're comfortable mentally. Even though the original goal of an accessory is as an aid to the physical game, it can become much more important to the mental game. This list is by no means every possible accessory you could have but it's a good start to making sure you have what you need.
You should have a bag in which you keep small tools and accessories. If you randomly place these items in your ball bag, you'll have trouble finding them when you need them. Searching for a pair of scissors or a piece of tape and holding up play can put pressure on you, not to mention that it is pretty inefficient. You might tend to quit looking or think you'll just suffer through the rest of this game without that piece of tape and fix it later. That never works. Here are the things we believe you should keep quickly accessible: Extra tape (multiple sizes), Fingernail clippers, fingernail file, glue, rosin bag, scissors, skin patches, tweezers, slick powder, 2 towels, bowling ball cleaner, an extra set of shoe laces, a shoe brush, a shoe protector for your slide foot and a small multi-tool.
Of course you can add to this list because you never know when you'll need a the tiniest accessory to enhance your game.