Looking for meditation techniques to boost mental performance

Hi everyone, I'm hoping to start meditating to improve my mental clarity, focus, and overall cognitive performance. My main goal is to get mentally stronger to help with my upcoming exams. I can devote about an hour per day to meditation practice. I was originally planning to do a 10-day Vipassana course, but unfortunately that didn't work out due to scheduling conflicts with my exams. So I'm looking for other meditation techniques I can practice on my own that could help with things like concentration, willpower, emotional control, decision making, productivity, and staying calm under pressure. Any suggestions on specific techniques to try? And how long might it take to start seeing improvements? I'd appreciate any guidance to help keep me motivated on this journey. Thanks in advance for your help!