Start by practicing a sequence just with your arms to get used to tutting. A good place to begin is with your arms straight at your side.
Move your arms up so they're parallel with the ground, creating a 90-degree angle between your arms and the sides of your body. Keep your hands straight and flat to create a perfect angle.
Bend your elbows so your forearms and hands point straight ahead. Now you have a 90-degree angle from your forearms to your upper arms as well as between your upper arms and your torso.
Bring your upper arms in so they point straight ahead. Keep your forearms in the same position in relation to your upper arms so they come in front of you , one on top of the other, creating a rectangle in front of your chest.
Pull the top forearm up and the bottom one down to create a space between them that's as wide as your hand. Bend your wrists to create a 90-degree angle between your forearm and hand.
Keep seeking out other 90-degree angles you can create with your arms and hands. Explore different positions to find your own style.
Add popping and other moves once you have the basics down to accentuate each tut move that you do and matches the musical rhythm you're trying to achieve. Also explore using more of your body to do a tut move.