If you get a chance, Get HP-plus materia!!... and have at least 1 person with Restore materia (i'm just the kind who equips every avaliable slot with materia)

Actually.. theres nothing much to say... just take things as they go... if theres a tough boss, come back later when your better equiped or after you train a bit
Save Alot!! that helps too

oh yes.. if your playing the first time... don't train aeris cuz (SPOILER)she'll be gone soon... rather, train Yuffie instead, cuz shes a long range fighter with decent magic abilities

so yup.. thats about all i can say. Gd Luck!!