To avoid laziness, first please completely stop using social media for two months before exams...they are a very reason to make you lazy to spend much time on internet and making you know unnecessary information.Second thing try to do yoga or meditation for at least 30 min in morning which definitely helps you increase your interest and concentration on studies.. Having proper and adequate sleep is must to avoid sleep during day time..After lunch have a small nap but make sure it's a small one like 15 to 20 min..It will definitely help you to stay active after lunch.And make group discussions if possible with friends at times when you feel sleepy.. Hope this information helps you at least for small extent.. All the best ankita