We aren't here to re-invent the wheel- here are some awesome resources across the web for learning:
http://www.footbag.org/ - your one stop shop for intro all the way to pro
https://www.reddit.com/r/footbag/ - reddit community
There are a great bunch of DIY videos on youtube, as is with everything.
https://joshuaclifton.com/juggle/ - might be the most comprehensive, attention to detail guides out there. From simple starters to multipanel and including ready to print patterns and sewing guides.