What to put in/on your fly fishing vest?

Forceps or multi-tool
Forceps or multi-tool is mostly use to squeeze of the barb of my fly hooks and makes it possible to unhook a fish much easier at times they took the fly a little deeper then expected. I use a forceps with the claw mouth in a 45% angle.

Clipper
To save my teeth and cut nylon.

Retractors

Amadou
I use it to dry my CDC flies.

Bite indicators
Essential for nymph fishing or when I need to present flies at a certain dept. I have two types of bite indicators with me in a small box. One series is colored and with very high floatability. In the middle I have put a plastic tube that fits perfectly on my leader tip! You just pull them up from the tippet and it's stocks automatically on the leader. The other bite-indicators are just small pieces of fly box foam with one self-adhesive side. I used that to glue this bite-indicator on my leader tip! (I never use it on my tippet)

Hook sharpener
I have always two hook sharpener with me. One for small hooks and the other one for larger hooks

Fly pad
I use mostly 2 self-made fly-pads one on each top pocket and replace them every yea

r.

Pocket lamp
I always have a small waterproof Maglite with me just in case when I fish longer then expected. It's quite handy when you have still a long or dark forest hike to do before reaching your accommodation or car.  

Whistle
A highly underestimate attribute. I ad this to my vest after I heard a story about a man who broke his leg while fly fishing and run out voice while shouting for help. The whistle saved his life. 

Matches- lighter
I always have some matches or lighter with me. I put them in a tiny waterproof bag. They often helped me out after I dropped in the water and used them to make a big campfire to dry my stuff.  

Tippet material
Depending on the type of fishing I have mostly 4 spools of different size tippet material.

Leader wallet

My leader wallet contents: spare leaders, a few special needles to make my own leaders, waterproof superglue to secure knots (I also use it a lot as a perfect replacement for plasters), a small scissor, a little bobbin with thread and some braided monofilament and backing for attaching my leader to fly line and emergency repairing on a fly line.

Fly boxes
Several boxes with nymphs, dry flies and other required patterns for the type of fish I am after that day. 

Floatant- sink
Floatant to use at my dry flies to keep them float longer. Sink I mainly use for fishing wet flies, nymphs or make my intermediate leaders sinking. I also use it sometimes to fish the tippet under the surface. 

Bug spray
Essential in buggy area's or mosquito heaven! 

Measuring tape
To measure a good size fish so you be sure you don't make a fool of yourself.

A little diary or notebook
I keep it with a pencil in a little waterproof bag to make essential notes about insects, hatches, weather conditions, water temperatures, air temperatures, fish behavior and when I change a certain fly pattern or just in case I suddenly get any good idea. 

Leader stretcher
Handy for those who use long tippets or self tied leaders.

Fly line cleaner
To clean and protect my floating lines from sinking

Thermometer
To complete essential notes in my diary

Small waterproof camera and spare film
For a lucky shot or nice fish

Polaroid glasses
Indispensable when sunny 

Leadshots
To let nymphs go deeper

Knife
Handy for all kind of things 

Retrieving protection
To protect my fingers while stripping or retrieving very handy for pike fishing. 

A boga grip or special gloves to tail slippery fish
I take this with me when I fish for slippery fish species. Very handy to tail so salmon as well

Licence
Indispensable... we don't want to fish illegal 

Toilet paper
You never know

Rain jacket
In the back of my vest

Life jacket
I take this with me while fishing dangerous spots or places while wading deep 

Spare spools
When I want to experiment with other lines or different depts.

Clothing