This is how to dress and do your make-up to look like an old lady for Halloween.
Steps
Apply some foundation to your face. Use a shade darker than you would normally use. Be careful not to apply too much or make it too dark!
Use brown eyeliner to make the wrinkles. Apply the fake wrinkles where wrinkles would normally be found; avoid areas that are obviously not where wrinkles form. Also, apply red lipstick, as some old ladies tend to wear lots of bright red lipstick.
Wear something from your grandma's wardrobe, preferably a dress or a long skirt with a blouse. Make sure it looks old and a little faded. Extra bonus points if you can find an outfit with old lady flowers!
Match your outfit with old-fashioned shoes. Avoid any shoes that look modern.
Tease your hair and powder it, so that it looks white or gray. Part your hair with a "middle" part. Tie it back into a messy bun or leave it as it is.
Wear fake but extravagant jewelry (it's better if it's gold). Pearl necklaces would fit and pearl earrings! However, be careful not to overdo the accessories.
Use a cane to help you hobble your way around, or one of those push carts.
Don't forget to use the 'old people lingo', as listed below:
broad
dame
gams
cat's meow
hooch
hotsy-totsy
killjoy
keen
spiffy
What's eating you?
Pipe down
Trollop
Tips
Walk bent over and in little steps.
Say stuff like "Back in my day" or "Before the war..."
You can also carry an old lady's bag.
To appear more believable, fake an old woman's voice and speak like old people do.