These are the tools I use the most for drawing football plays, both at https://joedanielfootball.com and for my own football team. Think I missed one? Tell me about it in the comments!
Here's the Top 5 plus where to find them...
5. Microsoft Office PowerPoint, you'll likely find it on your computer. Or use Keynote on a Mac or Google Drive for free.
4. CoachMe Football at https://coachmeapps.com/ or find it in the App Store.
3. Hudl Playbook Tool is under your Play Tools in your existing http://hudl.com account, if you already have access. If you don't already use Hudl, then you won't be using this tool.
2. Go Army Edge Football at https://www.goarmyedge.com/football but you do need to be in the United States to use this one.
1. Playmaker Pro from BW Software at http://www.bwsoftware.com/ for both Mac and Windows.