Striping is the easiest way to create a good looking fish hat. Just pick the colors you like and knit the stripes up while you go. can use a system:

  1. Roll the Dice method;
  2. Fibonacci striping method
  3. Random Stripe Generator
  4. use self striping yarn
  5. combine self striping yarns, uni yarns and one of the mentioned striping methods.

1. Roll the dice striping
Take a dice and let it decide how many rows you knit in one color. Roll a 4, knit 4 rows. Change colour, roll a 3, knit 3… You can also let the dice decide what the next color will be. Pick your colours and give each a number. First roll the dice for the colour, then for the number of rows you’ll knit.

 2. About Fibonacci striping:
Each stripe has as many rows as the sum of the two preceding stripes. Starting with 0 and 1 the striping goes like this: 0, 1,1,2,3,5,8,13,34 and so on. For your Fishy 34 and more rows may be a bit too much. From here you can count back, or start again with 1, 1, 2 etc. Visit wikipedia to find out more about Fibonacci.