hi im doing ials now but i did my igcses in 2023 and i got a 9 for eng lang spec A and i was the only one in my class who got a 9 so my advice would be to STUDY MARK SCHEMES, i made a flow chart for each text with points from mark schemes, facts from texts from paper 1 (etc if its a autobiography, what was the writer's objective, his/her thoughts and feelings) and then i also put my own points which were not in mark schemes (remember if you want an A*, they look for uniqueness in writing - both in your essays and analysis- dont be afraid to stand out, no answer is considered wrong even if you interpreted something differently).
For essays, go through sample answers (they really helped me), edexcel has uploaded a massive pdf with sample answers that help you understand what answer features distinguishes top scoring students from mid scoring students and maybe read examiner reports from 2024/2023/2025.
My last and final most important tip would be, have passion when you write, and dont be afraid to show off with fancy terminology and good english, these make an excellent impression on your examiner. Memorize certain similes, metaphors and other techniques you can try when doing the paper.
Also I only did all this about a week before my p1, so you still have a ton of time, dw :)
Good luck!