I recommend taking a class in kayak rolling but if you can't for some reason here are some tips how to learn to do a Sweep Roll on your own using a paddle float.
You don't need a swimming pool to learn to roll even though filming the steps in a pool greatly improves the video quality. Try to find some warm water (alternatively use a dry/wetsuit) which is about 1m or 3-4 feet deep to practise in so you can rescue yourself using your paddle against the bottom. Or of course if you have a paddle buddy beside you he/she help you with buddy rescue.
Even if you don't succeed to roll without a paddle float, you can make use of a 'float sweep roll' after doing a reentry. Faster and easier than climbing in!
NOTE: This roll is not suitable for white water kayakers. They need to learn to protect their faces by leaning forward during their roll. Parts of this sweep role may still be applicable but not all.
In the video I refer to viewing other YouTube videos for more specific 'hip snap' exercises, here is a an old but good one https://youtu.be/b_lGG_tOs5k?t=122 (hip snap starts at 2m2s).
Instead of a buddy's kayak bow, you can use a paddle float, pool edge or the shore to hang on to.
If you do succeed to learn to roll using my video, please comment below.
Good luck!
P.S. Make sure you have a strong paddle before using it for support during kayak entry/exit. I am NOT responsible if you break your paddle.
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