When you say ‘instructions’ do you mean the Heroku page entitled 'Using Amazon CloudFront CDN`?
If so, are you saying that Cloudflare does not have the functionality to do this in the simple way that is possible with Cloudfront, or are you saying that there are a number of steps I need to take on Cloudflare before I can do use the Cloudfront method.
Thinking about this further, I think you are referencing the Heroku page entitled `Using Amazon CloudFront CDN’. Unfortunately, I have not used Cloudflare for anything complex so do not understand your instructions. I someone able to give a step by step guide on how do this. Or is this the wrong forum to ask, should I try Stack Overflow instead?