Well here are some tips:
1/ be clear with all the vocab in both the shorter (restricted) and full (defined) list. You need to be able to do the full list from Latin to English, and the shorter list from English to Latin too. Watch out for irregular declensions or conjugations, and deponent verbs.
2/ learn your principal parts. In the vocab list, you'll notice not only the main word but also up to four more just to the right of it.
- For nouns, you'll also see the genitive form.
- For most verbs, you'll also see the infinitive, first person singular perfect, and a PPP (perfect passive participle) if there is one. For deponent verbs, remember that the verbs are only in the active voice, even though they look passive. There's no PPP for deponent verbs, as they have a PAP (perfect active participle) instead. You can find this by looking at the third principle part for a deponent verb e.g. 'conatus sum' and getting rid of the 'sum.'
- for adjectives, you'll usually see the masculine, feminine and neuter forms.
3/ learn your grammar. You'll see the noun declensions and verb conjugations in your textbook, as well as adjective endings and pronoun forms. If you use "Latin to GCSE" you'll find it in the reference grammar sections, or you can use the "language information" section in
Cambridge Latin Book 5 (free ebook if you follow the link). It might seem daunting, but it will be much harder if you're forced to guess what a word is trying to say from the context of a passage, than if you can immediately understand it because you know the grammar.
4/ on the language exam paper, you will notice an instruction to do
either question 10 (grammar questions) or question 11 (English to Latin). But
ignore it, and do both questions. It might sound crazy, but here's an inside tip from OCR about why you should do both: questions 10 and 11 are both worth 10 marks each. Very simply, if you do both, whichever question you get the higher number of marks on will count. So if you messed up the English to Latin and got only 2/10, but you thought the grammar questions were much easier and got 7/10, then you'll get the 7 rather than the 2.
I presume you know the structure of the language paper. If not, I can help with that too.