I fly every month, so I really have it down to a science.
Put anything liquid that you want to carry on in a 3 oz bottle and then all of your bottles have to fit into a quart sized zip lock bag. This bag has to be displayed at security by taking it out of your carry on and putting it in the bin where it can be seen clearly when it goes through x-ray. Things that you can carry on, but don't have to be in the bag, include lipstick, powdered make up/eye shadow, and eye pencils. You can also carry on nail clippers and manicure scissors that have a blade of less than 4 inches long. Tweezers are fine too. Things that have to go in the clear zip lock, in addition to the obvious liquids like shampoo, liquid make up, lotion and conditioner, are mascara and toothpaste. (Truthfully though, by mistake I've left my mascara inside my make up bag, inside the carry on suitcase, and it made it through security just fine without being in the plastic ziploc)
No liquids such as bottled water are allowed before you clear security. You can, of course, buy it after you are at the gate and carry it on the plane. Food will clear security just fine. I always carry trail mix or fruit with me from home.
Honestly, I have never tried to bring knitting needles, but I would guess they will search your carry on when they see them on the x-ray machine. Definitely make sure they are plastic, and then you can probably make it through with them.