Although english cannot be improved remarkably in a day, you can
try flipping through the dictionary and copying down new words.
Might help in your paper 1, you never know. =) I have this gut
feeling informal writing will be up.
As for paper 2, do NOT copy and paste from the passage. Use your
own words accurately if possible. Read up on summary skills,
summary stands 20/25 marks if I'm not wrong. ( I ABHOR SUMMARY!)

Comprehension is just comprehension(duh?!); understanding of
passage.
Anyway, usage of bombastic words is good but NOT too frequently
otherwise everything turns banal. Make sure you know the exact
meaning of word before using it.
My two cents' worth. =) More tips please! I need help too!