For live poker, I had the same problem when I started playing with some of my friends. One of my bros had some dead read on me that he still won't tell me about to do this day, but a couple things helped me fix this problem:
1) Find a comfortable position you like to be in and STAY THAT WAY the entire hand. Do not move. For me, I like to have my elbows on the table, left hand on top of my cards in front of my stack and my right hand in a fist covering my mouth with my palm facing to the left. This position works for me and I cover a large part of my face in the process. Once you find a position, DO NOT DEVIATE FROM IT.
2) When betting, whether value betting or bluffing, make sure you put the chips in the exact same way with the same hand in the same manner. I like to go for chips with my right hand, then almost sliding them forward so that the dealer and Villain(s) can see what bet I made.
3) DO NOT TALK DURING A HAND. You are not Daniel Negreanu. You're more likely to give away information or
tells about how strong or weak you are when you open your mouth. Talking for the sake of getting a reaction out of your opponent is risky too, if your live tells are not up to par. I've sometimes got them to work, but other times they've backfired. So as a general rule, just don't talk during a hand.
4) Pick one spot on the table to stare at when making a bet and trying to remain unreadable. I normally pick the window card on the flop and once I've made a bet, I just stare at that card without moving and maintaining the position I mentioned in my first bullet point. This helps keep our entire body still, motionless and our eyes from giving away any information about our hand strength. Especially if Villain tries to angleshoot with his chips or anything else along those lines, I will not see it because I am focused on that one card and do not take focus away from it unless it's my turn to act again.
These are some general rules that helped me make myself harder to read and it has worked for me so far. Not to say you can't be friendly and open at the table, whenever I'm not in a hand I'm more than happy to chat it up with the people around me. But once we're in a hand, I shut it down and go into full on frozen mode
lol good luck on the tables, hope this helps!