Need help to improve quant speed

Hi, I'm pretty comfortable with Arithmetic and Algebra and can do the basic or easy of Geometry. For the past few mocks. I'm scoring around 20 in QA. My accuracy is almost always 100% but I cant seem to improve my attempts. When I later analyze the mocks, I had missed 2-3 easy questions because I could not only reach till the last question. I do follow the round strategy. I think my problem is that I dont know the optimum method of solving some sums like time saving tricks. Can anyone please suggest me ways to improve. I am targeting 30 in Quants.