Working with cash and making change, especially for people who don't work with cast daily, it can be a stressful time... making sure you give the correct change and not keeping people waiting. One of the things that can be be done is just making your cash more accessible and easier to see and count, just the same way retail clerks give change from their cash registers... with a cash tray.
These are easy to make, but they do take a bit of time because there are a number of components, and you don't want to make they too big. The best way to start off is to determine how many slots for cash bills you want, and what the size of your money is. The size of your money and how many bays you want will determine the size of your tray and keeping in mind you may also want some change bins in case you are dealing with coinage.
Watch this and other similar videos on YouTube - https://youtu.be/2eUhWhZWg8g
I mad mine 2-3/4 inches high and that was plenty, I think 2 inches would be a better height if I ever had to do it again. I decided on 4 bays for paper money which also meant 4 bins for coins as these were used for the spacing with of the box.