Here is a Utube Video that gives a quick intro. https://www.youtube.com/watch?...
And this webpage will tell you everything you need to know...and a lot more. There is so much detail you might want to skip a lot of it. About half way down the page is a section called How To Cross that gives you one hybridizer's (Don Spoon's ) method for making crosses.
There are lot's of Utube videos and websites if you do a little searching. It's really pretty easy.
Good Luck and Welcome to ATP's Iris Forum. Come back and visit....you can learn a lot from these people!!!