Quantitative aptitude is considered a tough section by people who do not have a background in Mathematics learning. Even though it seems really tough with proper guidance and understanding basic formulae and math tricks you can easily perform great in this round. You just need to have the knack to look at each question with a unique viewpoint and that you can only learn with practice.
Here are a few tips that might help you perform better :
Start by working on the basics, once you have your basics clear and you have the understanding of important aspects nothing is difficult. Everything is linked to one another, make sure you don't out any base-level formulae and tricks. Do not rush. Take your time with it.
Be systematic when learning, start by learning one thing, and trying to solve questions related to that. That will help you fit all of it in your brain.
Know your strengths and weaknesses. By doing so you will know where you should dedicate more time
During a quantitative aptitude test - Time is the key. You have to ace the shortcut techniques in order to be able to solve all questions within the time frame. Never take these lightly.
The key is to focus on concepts and not just solving questions. If you know your concepts well you can solve any question thrown at you.
Always try to decipher the question well, do not go by instincts here. If you have understood the question then only go ahead and solve it
Last but not the least, anything can be done if you practice enough. Keep practicing every day and that is definitely going to make you perfect here.