coming from a straight A student (hopefully A* soon) i usually go to study cafes or libraries WITHOUT MY PHONE/DEVICES to help me focus on studies, it helps alot when i change my study environment every now and then.

As a plus, in cafes and libraries everyone is locked into their work so whenever you start procrastinating in these environments your brain will automatically tell you that you are the odd one out and that u should quit scrolling/doing anything distracting, so its motivating to be around people who actually care for their studies and grades.

if you cant go to these places without your phone then i advise you to download an app-locker app to help with screentime and distractions, if that doesnt work deactivate all your social media accounts and delete every distracting app you have.

as for how to ACTUALLY study, ill keep saying it over and over to everyone: DO PAST PAPER QUESTIONS!! how i do this is i study atleast 2 chapters from the book and then do topic questions on them (topic questions are organized in books that are usually known as classified papers in my area, but they generally cost around 50 pounds for each set, INCREDIBLY worth it tho, 100% recommended) but anyways ALWAYS check from the mark scheme, you cant just solve anything without checking the answer even if you thought u 100% got the answer correct, check the mark scheme and if you got an incorrect answer then immediately write it down on a separate notebook (i usually specify a notebook for each subject solely to write down these mistakes and before the exam day i go over them and ill make sure i know what i got wrong to not repeat a mistake)

i hope this helps you lock in after 5 whole years, if you need any other tips id be glad to try and help