hm i for my part dont like alarms that much. i used them at the beginning to do a major WBTB after 4-6h of sleep but in my opinion its not that hard to notice the awakenings with enough intention and its way more natural. you wake up after REM and most of the time wil lremember dreams without to much effort (just dont fall asleep while remmebering again xD). with alarms you probably wont hit the exact moment so you wake up during a rem or something so your recall will suffer and it breaks up your sleep more in my opinion. but i read that a lot of people use alarms and it seem to work too...

i would try for a week without alarms and just set a strong intention to wake up often during night. after a week when you dont see ANY progress you can try with water or an alarm.