Okay, a couple of common points of confusion to iron out (hopefully) today.
Me vs. I
Lots of people have their own ways of thinking about this. For me, it comes down to what makes sense without the 'you'. If deciding between 'you and me' or 'you and I', say the sentence aloud just with the 'me' or 'I' to see which makes sense. E.g.
You and me both like books.
Take a look without the 'you' and you'll have 'Me (both) like books'. Clearly this makes no sense; therefore, the sentence should be:
You and I both like books.
Who vs. Whom
This is another one that relies on verb form, but there is a quick way to decide which it should be.
The man who he loved.
Reverse the sentence and see which fits best: 'He loved he' or 'He loved him'. We can tell at once it should be him; therefore, the correct wording of the sentence would be:
The man whom he loved.
If you'd say 'him' rather than 'he' (or 'her'/'them' rather than 'she'/'they') then you know it will always be whom.