It often ends in failure and has more chance of success after a few REM cycles (about 4.5 hours or 6 hours after going to bed at night). Still for most people it's quite an effort at 4:30am (including getting up at that time and the WILD 'entry' concentration effort) and chance of failing is high. Often people will do this on weekends as it can make you feel sleep derived if you have to get up for school or work. If at times you do it naturally without effort then that's great.
There are smartphone apps that can help, a simple one is 'sleep cycle' alarm (not actually designed for Lucid dreaming - though some apps are). This movement based alarm that sounds near the set time when you naturally move/wake from REM - set it to go off about 4.5 or 6 hours after going to bed.
Warning: WILD entry phase (conscious sleep paralysis) for many people can be the most fearful and extremely unpleasant experience they will ever experience in their life (it depends on the person, their imagination, their life experiences, mental/physical condition, belief systems etc). Sleep Paralysis a natural thing and we do it multiple times every night but we normally do in a unconscious state (so it's not scary and of course not noticeable at all). It can be scary stuff (when conscious), though reportedly not life threatening (though it can feel/look/sound like it is )
Some people get through it relatively easily (some even say it's pleasant) but most people are scared to some degree even when are used to it.
If you make it past there - the dream state you enter can be fantastic.