1. there are a lot of different techniques... may I refer you to the tutorial section?

2. reality checks are a way of finding if you are dreaming or not for a reason... the results are so different from the logical result you'd get while awake that it is impossible to be able to mix it up.

3. some people claim the vitamin B6 and Melatonin work wonders.

4. you could... but I don't know the point of LDing without being able to remember it in the morning. again, DREAM RECALL IS NESSECARY