You only have one mode of control, that is your mouse. Your mouse controls a white circle which the head of the hammer will follow. While you can adjust the sensitivity to your liking in the pause menu I would recommend going with the higher end of the spectrum. You may find it to be a little jumpy, but it makes movements that need to be made on the fly in make-or-break situations much easier. Mess around with it as you see fit, don't be too afraid to try new settings.

Throughout the game you'll notice there's a lot of different ways to jump, hurdle, and climb. While there's countless different techniques and maneuvers used to traverse in the game, there's five very basic types of locomotion that I feel are essential.

Push Jump
The Push Jump is exactly what it sounds like, it's the most common move in the game by far and hardly needs an introduction or an explanation. But here one is anyways :) So to perform a push jump you'll need to place the head of the hammer on the ground below you, adjusting the angle where the hammer hits the ground will allow you to jump in different directions. A slight variation of this jump would be to lift yourself off the ground and swinging into the direction you wish to jump and once you reach your desired angle you jump. The added inertia from swinging can give you a the few extra inches you need to clear an obstacle in some situations.

Pull Jump
Again, exactly how it sounds. You'll want to be hanging from some object, or have your hammer on top of some object above you, and you'll simply pull. I find it's helpful to have your hammer resting closer to the edge of whatever it is you're using to pull jump off of. You also won't want to pull straight down, often times this will smack your head right into the object you're using to pull off of. And then you're gonna fall. And then you're gonna be mad. I'd recommend doing a kind of half circle shape as you pull down, just to be sure you're going to clear whatever it is you're pulling.

Lift & Lower Climb
Almost a combination of the pull jump and push jump, the lift and lower technique of climbing is invaluable for beginners. It's the lowest risk method of climbing by far, however it can be quite slow and very tedious. The way this method works is by lifting yourself up slowly from an object above, setting yourself atop that object, and then reaching to another object above you and repeating. Often times you'll need to perform a push jump to reach the next object. If this is the case I recommend push jumping, and then immediately and smoothly moving your hammer to a catch position on the next object. Then you can lift yourself up to it, lower yourself down, and repeat! It's all in the name.

Swing Climb
This one is used heavily by most gold pots and speed-runners, and it's no wonder why. It's fast, and it looks damn good... Even if it's pretty dangerous... To do this one, imagine making multiple circles with your hammer and using each rotation to grab hold of the next object and simultaneously moving yourself upwards. This method is dangerous for the same reason it's so fast. You never stop moving. You carry your momentum all the way from the bottom of the obstacle clear up to the very top. Unlike the lift and lower method, you're not going to be stopping to think before every jump. You'll just swing yourself up, catch, and repeat. Of course a combination of both the lift & lower and swing climb is usually ideal for most players. On the easier parts of the game swing climbing is worth the extra risk, but on the harder parts it's probably worth while to take the extra time with the lift & lower. However there are a LOT of variations on this one, when you watch some of the really fast guys play you'll notice their hammer stays almost completely horizontal as the cruise up the mountain with ease. They can do this because their momentum is so high they don't need as much force on each individual swing, and usually each swing is just to maintain that momentum and make slight adjustments.

Bucket
You may think you know how to do this. But you don't. Just sit there, throw yourself at the bucket, and suffer.

Tip 1: The most important tip I have is to take it slow, getting greedy and attempting to throw yourself halfway up the mountain with one ill-advised swing is a recipe for disaster.
Tip 2: Stop when you have the opportunities to asses your options, it's important to get a mental image of the movements you want to make before you make them.
Tip 3: Don't be too afraid of falling. It's going to happen one way or another on your first try. Embrace it, find humor in it, don't take it too seriously.
Tip 4: Take a break. Don't force yourself to keep going if you just don't have the patience for it at the time. This is a game I wouldn't recommend trying to finish in one sitting, it's a marathon. Remember that.

Survey says that more than half of the game takes place in your mind... At least that's probably what they say... So here's some mind armor for your brain.
Mind Armor 1: Remember that you will get there sooner or later if you just keep going, it's only a game however, so don't hurt yourself.
Mind Armor 2: Listen to some mellow music, something like King Krule, Low Roar, Slenderbodies, that kinda thing. Whatever works for you to help take your mind away from rage.
Mind Armor 3: Make sure it's just you and the mountain. Don't go into it while you're waiting to go do something, that's just too much pressure. Silence your phone and put it far away. Concentrate. It's just you and the mountian.
Mind Armor 4: Chew on some gum and have a drink with you. It doesn't have to be gum obviously, you can go full on Doritos and Mtn Dew if you want... Actually Mountain Dew is oddly fitting for the task at hand...
Mind Armor 5: Celebrate the small victories. If you get back to a spot you just fell from take pride in that, but not for too long. There's bigger fish to fry.
Mind Armor 6: If this isn't the game for you, you'll know pretty early on. If that's the case then refund it and move on, you have nobody but yourself to answer to.

This is not an easy game, and I wouldn't call it fun. I'm not entirely sure I'd call it a game either. It's a challenge... A challenge that you can conquer. Hopefully this guide encourages you to keep climbing, and hopefully you'll get over it.