I’m concerned that I may be developing some bad habits with regard to how my mouth moves or tenses sometimes while I’m playing. This is the one area of the Beginner to Boss online course that I struggle with since Luke can’t actually see my technique and correct me. It seems that in order to achieve decent notes from certain holes (e.g. 2 draw, 8-10) I have to contort my mouth a bit, then when I move back to less challenging holes my mouth is not properly positioned for them. When I watch Luke playing, his face seems completely relaxed, and his mouth doesn’t appear to contort or strain in the way I feel mine is doing. Is this something beginners struggle with and will naturally improve over time or is this something that I should work to remedy now? Appreciate the feedback/advice. TIA.
I think its just practice. Muscle memory needs to develop quick responses. I only recently realised i get -2 without even thinking. Some bends start the same way first it seems you have to contort the inside of your mouth to get it but then you just do it on auto pilot one day. Just practice.
I just went through a bout of this. I watched a video on U Tube and the player said the following ,which helped me. Luke has a good u Tube post on this as well.
Place the harp in your mouth tilted slightly upward. The upper lip should fit into the low spot on the face plate and its basically along for the ride.
The harp should be back in your mouth but not enough to hit a tooth.
The lower lip is the should be placed over the bottom plate with the moist portion of the harp relaxed. The harp should hit the corner of your mouth to avoid air seeping in.
Before placing it form you lips like you are going to whistle. Relax and keep your tongue flat. Its the lower lip that you create a small hole with to isolate single notes.
I had to learn the hard way as I was not placing it far enough back and the low humidity caused the lips to dry and drag as I slid the harp to another note. Luke also has a U Tube post of this issue as well and I learned from I suggest you watch it. He did say to insert your finger behind your lower lip to make sure its relaxed.
I also hated the high draws and I suspect you are hitting them too hard as I was. The more you play like this the quicker you can break whatever habit causes you high end draws. I am friends with the right side of the harp now but do feel they will always be the notes that are a bit more difficult but practice tunes with numerous -8 and higher draws. This is what got me to the point they are not so tough. Keep a cup of water beside you. I am also a believer harps and humidity and chili whether as not friends. I put a second harp in a place that will keep it warm. On chili days the harp seems to be tougher to play. But this is only my opinion.
On your closing questions I fell the answers are yes and yes. Grooving a bad habit will slow your progress. Luke commented that you draw a high note about as hard as you would blow a lite candle without putting it out. This is about as good as one can get explaining how to play them.
One a final note when I use my lower lip to isolate a note and the harp is far enough in single notes get cleaner. Good practice cures about everything.
Hope what really helped me helps you.
Relaxation is key. The low notes are tricky and sound a bit off at first. Relaxing the breath will help. You want total relaxation of the face and neck when playing. Nothing on the harmonica requires force.
Same here, it’ll come with time.
I remember starting out and my lips and cheeks would be aching after practice, now it’s light as feather after an hour of playing.
it’s hard to “be relaxed” whilst also trying to something that is quite hard to do at first, but it gets easier.
@marcy0711 welcome to the forum! You’ve gotten lots of great replies here. Yes, the maxim is: try…and try again! And of course also: tension is the enemy of mastery.
We always too much force when we are first learning a new thing and then gradually we can relax into it more and more.
But “strive” for relaxation. 
Also, video yourself upload to YouTube (you can keep the link private if you want) and share the link here. I’m happy to give you feedback any time!
Rock on! 
I appreciate all the thoughtful responses and advice. I have completed the first three modules, but before I move on I think I’m going to go back to the beginning, really focus more on technique and staying relaxed. I love this instrument and I’m loving learning how to play it. I’m having so much fun. Thanks for a great course, Luke!
So smart! Can’t be too secure in the fundamentals. The value of developing the habit of relaxation cannot be overstated. Rock on!
I spoke with an older life long player, he told me that you can not have a good embouchure with the pursuing method. Can any one confim this? My next question is, which exercise can i do to build embouchure techniques? Thanks Eric.
Not true! There are many super advanced and pro players that do not tongue block! I know many personally and trust me. There is no right or wrong embouchure.
Thanks DK, Can you recommend any exercises to improve the techniques? Eric
@lasersolutionswi You’ve had your first (of likely many) encounters with the Tongue-Block Police. 
@KeroroRinChou can tell you all about them!! “You’re not really playing harmonica if you’re not tongue blocking.” You can learn to tongue-block when you want to, and then compare the tone of your lipping with your tonguing. But you’re doing great man. Just let it slide off your back and keep having fun.
And that person is wrong. As somebody who has encountered so many people like that in so many times in my life as a (mostly) lip purser, I’ve heard everything in the book. I’ve heard things like “lip pursing causes wrinkles”, “you’re limiting yourself by being a lip purser”, “you can play everything with it”, “you’re gonna miss out on so much”, et cetera. I’ve found out that a lot of tongue blockers, especially those use it full time, only talk about the negatives of lip pursing and only the positives of tongue blocking. I was even told I was lazy for not “learning the harmonica correctly” by a purist once.
I only use octaves and slaps, but I use tongue blocking more as small tool instead of using it full time because tongue blocking exclusively limits my expression. My playing style relies on a lot of bending techniques like growling, which is easier to achieve (for me) lip pursed, and I like to really dig into a phrase and just wail on the harp, so tongue blocking would not be very ideal for me.
For tongue blocking?
Lip pursuing
This is not my specialty. I teach tongue blocking exclusively. Apologies.
Once i master pursing, i will tackle tounge blocking. Having a difficult time using my tounge for octives. Its a brain trainning thing like rub ur belly and pat your head… 
in time i will get there. Thanks DK.
Excellent! I’m here for ya!
@lasersolutionswi the Big Tone Train will improve your tone lip blocking. The key is too big and round in the back of the mouth. Think “uh” vowel shape back of tongue lowered and soft palate raised (like it does when you yawn.) The bigger the chamber in your mouth, the warmer and rounder the tone. That and of course the nice DEEP relaxed mouth position. DEEP SEAL + BIG CHAMBER = GOOD TONE.
Later on when you learn TB-ing you can compare the tone of your lipping with your tonguing and try to get it to sound more like tonguing. But meanwhile - Big Tone Train is your friend for sure.
For sprites, the Tongue Block Trainer is invaluable if you’re struggling with it. Helps so much to literally see what’s going on.
Hope that helps. Rock on!