Past paper marking - A level maths OCR

I have noticed that on the mark schemes for past papers that I have been doing, I often go a slightly different route but get the same answer, for example, on a mechanics question, I might find displacement as negative and just say the distance is the positive version of that, but on the mark scheme, they use a way that gives a direct positive, giving the same answer. My teachers are super harsh in mark schemes, so I was wondering if an actual examiner would give the method marks for that, or if not, and if so, how to know what methods they want, as I have even seen some mark schemes say that no marks are given for certain methods e.g polynomial long division. As I do not want to get a false impression of how I will fare in exams, I was wanting to know, typically, how strict marking is at A level (Particularly OCR maths A, as that is the one I do), as I have honestly just got into the habit of writing even the most insignificant steps just in case, but of course, this is a huge time sink, so I was wondering how far you need to go in terms of showing your work, as I do not really have a good idea of how papers are marked; I even had a paper once where I got absolutely everything right, but lost marks because of method marks, so I am concerned it could affect my grade, any advice is appreciated

In mechanics as long as you define which direction is positive you'll get full marks.

Why would polynomial long division get no marks? Can you link that mark scheme?

If you do a valid method and get the right answer you will not lose method marks.

Ah ok, that makes sense, my teachers are probably just being overly strict then, thank you for the advice

In regards the specific question, it was question 4a on the 2020 mechanics AS paper (In the guidance section on the MS):

QP: https://www.physicsandmathstutor.com/pdf-pages/?pdf=https%3A%2F%2Fpmt.physicsandmathstutor.com%2Fdownload%2FMaths%2FA-level%2FPapers%2FOCR%2FAS-Paper-2%2FQP%2FNov%25202020%2520QP.pdf
MS: https://www.physicsandmathstutor.com/pdf-pages/?pdf=https%3A%2F%2Fpmt.physicsandmathstutor.com%2Fdownload%2FMaths%2FA-level%2FPapers%2FOCR%2FAS-Paper-2%2FMS%2FNov%25202020%2520MS.pdf

It is a small question, but it is one of the examples I can think of where some method is not allowed for some reason, I cannot recall exact questions but I believe I have seen a couple other ones where something similar is done, but for the life of me, I have no clue why.

Thank you for the advice!