Aggressive climbing shoes are shoes with a downward curve, many times also with a twist towards the big toe.

This downward curve allows the climber to exert maximum power through their toes, allowing them to have more force and stability, and to be able to stand easier on bad foot holds.

Aggressive climbing shoes are also the popular choice for bouldering, since they tend to be less comfortable than neutral or flat shoes, which mean that climbing in them for a longer period of time could be quite painful, which makes them less popular for sport climbing. They are also a great choice for overhanging climbing as they tend to excel at gripping holds, allowing the climber to keep their body closer to the wall and to keep their feet on the holds.

Eventually, as the shoe is used more and more, the curve loses its shape, and the shoe become straighter.

Climbing shoes are meant to be as tight around the feet as possible. This insures that the feet will not slip inside the climbing shoes, giving the climbers a much better grip and control while climbing and standing on difficult foot holds, and while performing difficult moves such as pulling their body weight with their heels.

Wearing socks can hinder this tightness around the foot by creating an extra layer between the foot and the shoe. This can cause the foot to move slightly inside the shoe, which can reduce the climbers performance by reducing the efficiency of the shoe. The efficiency is reduced because climbing shoes must be as stable as possible on the climbers feet, meaning, if the feet move around inside the shoe, the climber may not be able to exert the required force they need, such as when pulling your weight on your heel. If the climbing shoes are not tight enough, the heel could move inside the shoe, and even come out.

While the climbing shoe should be as tight as possible, this does not mean that they must be painful. There is a limit to how tight a climbing shoe can be without it causing pain. It is important for everyone to try out different climbing shoes and different sizes to find the shoe and size that fits their feet the best.

Your toes should be slightly curled in climbing shoes. This gives you extra power and accuracy when standing on your toes on small edges. It also allows you to be more precise with your footwork by being able to stably place your foot on holds and in positions that would normally be much more difficult.

Having curled toes also helps you feel the holds better so that you are better able to trust your feet on poor foot holds.

The amount at which your toes should be curled though depends on the climbing shoe, and on your comfort/pain level. Just like the climbing shoes themselves, your toes should not be in pain and should not be painfully curled down. For many shoes, the curl will be a very slight curl where the tips of your toes are slightly pointed downwards instead of straight forward. In other shoes, the curl may be more aggressive, with the tips of your toes pointing directly down.

Climbing shoes are important because they give you the much-needed friction on the wall and on the climbing holds. Their main benefit is the performance boost they can give you.

Climbing requires a lot of precise footwork. This precise footwork cannot be done with regular sneakers or sport shoes. Climbing shoes are designed specifically for climbing, whether it's the material the shoe is made of, or the shape of the shoe, it is all calculated and designed to give the climber the best performance possible while climbing.

While shoes are not a substitute for proper technique, body positioning, and the understanding of your body on the wall, climbing shoes give you that extra stability and variety when it comes to moving on the wall that cannot be replicated with any other shoe. This comes into play with toe hooks and catches, heel hooks and general heel usage such as pulling on the heel, standing on tiny edges, and slopers.

As you scale up the climbing grades, progressing from one grade to the next will be more difficult for each new grade. It makes sense that reaching and climbing v9s consistently will be harder and take longer than it did for you to reach the v8s. The same will be for when you want to go from v9 to v10.

If there is a certain project you are working on, try to understand what you are not succeeding in. If it's a specific move, try to practice and train for that specific move until you can do it on the actual route. If it's a difficult hold or body position, train specifically for that.

The point is to break up the route into smaller pieces and to work those out until you can do them on the route itself.

If you can do all of the moves, but have difficulty putting them all together and doing the whole route, try to do it in sections. Try doing half of the route from the start, and the second half from the middle till the end. Or, if there is a specific point that is difficult, try doing the route until that point from the beginning, and then from that point until the end.
Another option is to work a small section with that just point in the middle, so that you are working on that difficult point specifically.

The point with this is to try and improve the moves that you are currently able to do, and to figure out different options for the moves that are difficult.

Squats are a great overall leg exercise. The exercise really hits the major muscles in your legs that can help with climbing.

You don't even really need to add any weight to this exercise. Depending on your goals, if you just want to improve your leg strength for dynamic movements in climbing, even squatting with body weight can be enough.

If you want to go that extra mile, you can do a jump squat.
A jump squat is when you do a regular squat, but as you rise up, instead of just standing up, you jump as high as you can. This can help give you that extra strength training to get better at those dynamic climbing moves where you have to jump and reach a far away hold.

Other than squats, calf raises is another great exercise. All you need to do is to find a step or an edge to stand on with your toes, and you just raise yourself as high as you can while staying on your toes, and then you just lower yourself until your heel touches the ground. The higher the surface you are standing on, the lower you will have to go to touch the ground, which means it will be harder to complete the exercise.
If you feel that it gets too easy, you can hold a dumbbell or any other weight in one of your hands for extra difficulty.