Hello! I'm gubb, I've been mewing for 3 months as well lurking here, and  I just wanted to post my experience and my results so far since this is mostly an anecdotal practice.

Pre-emptive FAQS

Routine?

Mew all day erry day. Chin tuck whenever I remember to do it. Mouth shut and  teeth sometimes in contact, sometimes not in contact. My lips like to open slightly when I stop thinking about what I'm doing but I always go to sleep hard mewing. 

I chew 2 hours a day 30 minutes on each side with Mastic Chiox Gum while I play Overwatch or watch Youtube.  Chiox is expensive as all hell so I basically chew the same piece every day for a week to get my money's worth... unfortunately I cant go back to Falim cause it's too soft and I cant feel the burn. I chew Falim if I have no choice or I'm out and cant get to my Chiox

I'm just starting out was it hard? did you experience this? etc etc 

Yes, your mouth will be dry and uncomfortable and filled with slightly too much saliva for the first month. Yes, you'll wake up with your tongue not at the roof of your mouth. Yes, parts of your mouth will be irritated. Yes, you'll feel like your gagging when you first try to breath through your nose while your back third is up. No, I don't think that growth inside your nose is something cause by mewing please go see a doctor no one here is a doctor.

P.S i had popping while i first started chewing  so i did 2 pieces of falim(one on each side at the same time) for a month to get my jaw strength up and now i just chew a wad of chioux gum on each side and theres almost no popping

Intermolar Width?

I didnt really measure! I just took some floss, placed it against my teeth and then took the floss and put it next to a ruler to get a general idea of what I was working with. I'm around 40mm inter molar 

Do you open mouth chew?

I'm not sure why this has become a meme on this forum but unfortunately I do a mixture. I usually chew gum while playing video games or working and ill end up chewing with an open mouth without realizing it 

Diet?

For that one guy whose always asking I eat broccoli and kale and shit like that but that's mostly because I want to get a food tan and not cause i think it'll do anything for my face

Why did you start?:

I shaved my beard and saw how weak my jaw/chin was as well as how asymmetrical I am  and it sent me down a path of spiraling insecurities.

How long did it take you to understand WTF Mew was talking about?

Half a year honestly. I thought I had been mewing for a few months before I realized I only had the tip of my tongue on the roof of my mouth. I think on one hand Mew is trying to describe a difficult thing to grasp and on the other hand he rambles on for way too long and muddies his own point. 

Braces?

Yep had em still have some permanent ones on the back of my lower front teeth.

What i've noticed section:

1: When i chew my Temporalis gets really roidy near the side of my eyes and starts to make contact with my glasses 

2: I think the act of chewing has improved the circulation of blood to my beard so my weak patchy side feels less patchy now

3:When i take selfies its easier for me to find an angle where i have a square jaw 

4: For the first month i was so distracted by trying to keep my tongue on the roof of my mouth that i would do weird shit like leave my car keys in the refrigerator without realizing it

5: I can flex my jaw muscles and wiggle my ears now.

6: My last wisdom teeth that didn't even seem close to wanting to pop out started emerging after i started chewing

Heres a picture of my eyes I have a beard rn so I dont think itll do anyone any good to compare a shaven picture with an unshaven picture. But you can see my ears are  moving all over the place and my left eyebrow jumped a bit too