Hi guys I actually tried WILD this morning after waking up, and I felt I almost reached SP but not quite the main problem was that I was breathing through my mouth and I kept gagging should I take breaths through my nose? And when you enter SP how from there do you enter the dream? Do you instantly become lucid e.g not lapse of consciousness? And finally can I try it as I am falling asleep or in the morning? 
A video about how to stop swallowing reflex, I assume that’s one of your problems here.
youtube.com/watch?v=hljU1TQxmKk
Yes, I would advice you to do that. I myself always do WILD with mouth closed. By the way, it is helpful if you do the nose RC. If you fall asleep with your mouth open, the RC might mess up.
I personally stay relaxed. I observe the images and find myself in a dream quite quickly. The more you relax, the faster you should fall asleep. Sometimes I even risk a little bit, relax too much and lose consciousness for a few seconds and regain that consciousness when I am already in a dream.
It actually depends on how you do the WILD. All people are different and everyone does WILD as they feel it’s best for them. Some stay conscious from the start to the end, others (like me) drift between consciousness and unconsciousness, sometimes even losing consciousness for a brief moment. I advice to simply experiment with WILD. I cannot tell you what it will be like, because, as I said, it is different for everyone.
It’s best to do it after WBTB (after 4.5 - 6 hours of sleep). That way you will enter the REM phase directly without having to wait much in NREM sleep. WILD’ing at night will probably be a headache, since you will have to wait around 90-120 minutes in NREM sleep. And it isn’t worth it, since after this long time you will enter the first REM phase of the night that lasts only a few minutes.
Here’s a very useful tip for WILD (if you’re planning to do it when going to sleep): Be very tried. How? Get up some hours earlier than usual (if you have a schedule), work out hard, go for a jog or a bike ride - just get really exhausted. Once you hit the bed in the evening you’ll fall asleep a lot faster than usual giving you a huge WILD-boost. 
The following is pure experience. I find it to work better than when waking up after 5-6 hours with WILD - in fact, for me, WILD only seems to work this way, so you could give it a try. 
The mind experiences three types of tiredness (or so I believe): Short-term tiredness, Sleep deprivation and Mental fatigue.
1. Mental Fatigue is when you get mentally tired, as in, if you read too much or watch too much computer or TV. That’s a bad and unnatural form of being tired and causes what Nick Newport calls ‘brainmush’. 
2. Short-term tiredness is simple muscle exhaustion. If you go to the gym and do +10 bicep curls of 20Kg, your fast-twitch fibers will fill with lactic acid (or whatever it’s called), you’ll feel very sore for a moment and you won’t be able to do another rep if you don’t rest for just a little bit. If you rest 2 minutes after this though, you’ll be as good as new and able to do another +10 reps. This is short-term tiredness.
3. What we are aiming for though is the long-term fatigue. This happens when your slow-twitch fibers are being exhausted. Now this happens in a prolonged compact exercise, such as running, riding the bike or even walking a long distance. You’ll feel after, say 2h of non-stop walking that your calves get sore and your feet start aching. That’s long-term tiredness. Why are we aiming for this? Because the subconscious mind understands this as sleep-deprivation. When you are sleep-deprived, your REM cycle flips on almost instantly when you fall asleep - no more 1-2h waiting. The same feeling is reached with what I call long-term tiredness.
The final idea is to want to go to sleep not for the sake of trying WILD or having a LD, but for the sake of being so tired that you want to get some well-earned rest. This triggers REM a whole lot quicker than when going to sleep after a boring working day, where all that you did is just sitting in your office and doing paperwork. 
I wish you the best of luck,
Cheers