Input hypothesis explained
The Input hypothesis (i + 1) suggests that learners progress faster when they receive input (i) that is slightly above their current level (+1). An easy way to explain it would be to take new information (words, expressions, phrases) and include them to already understood concepts. Professor Krashen says that using this method, "both comprehension and acquisition will occur".
Input hypothesis applied
1. Identify if the material you are reviewing is too easy, too hard or just the right difficulty for your current level. There is nothing wrong with reviewing easy English material, but don't expect to improve too much if that is all you read. Always try to learn new things whenever possible.
2. Keep a list of words or phrases that you need to review. You can review them individually, even better if you review them in context (when they are attached to sentences).
3. Find time to be consistent with your English practice. The more you practice, the better you become.