Water works good for me... Well, about alarm:

When should i set it if i want to wake up after every rem cycle? i've heard that every rem cycle continues for about 100 mins... So, when the first cycle comes? After 4 hours falling asleep or so? than i just add 100 mins from that time when first rem cycle comes and i set alarm when i wake up, i write my dream and i set alarm after 100 mins again.. And all night like this

So, when the first REM cycle comes ?