Traditional Greek Gyro 

Ingredients:

4 Greek pita bread rounds
tzatziki
1 large onion, chopped
2 medium tomatoes, diced
Slices of Gyro meat
(eyeball it, but about 4-8 slices per sandwich depending on the size of the pita)
Dried oregano to garnish

Place a piece of aluminum foil down on a flat surface. 
Place a round of pita bread over the foil. 
Spread tzatziki across the middle of the pita bread. 
Top with chopped onion, diced tomato and then add the gyro meat. 
Sprinkle more tzatziki over the top, if desired. 
Also sprinkle some oregano over all the ingredients.
Roll the gyro sandwich and wrap it in aluminum foil so it can hold the shape. 
Repeat until you've used up all the bread.