Hi, newby here.
My take on the old lady look - tightly curled perm or stiff shampoo and set, face powder that is too light and lipstick that is too dark.
Any kind of top or blouse, as long as it's too big and tucked in, extra points if it is paired with a fleece or padded gilet.
Elasticated skirt or trousers. Skirt to be midi length and pleated; Palazzo trousers or sweat pants at half mast. Think sack of potatoes tied in half.
Pair with beige ankle socks, pulled right up and black leather slip ons with a slight heel.
Bag must be faux leather, fabric or oilcloth, patterned and worn cross-body.
Cheap oversize costume jewellery for added effect.
I must say, though, that I see many chic ladies out and about, who wear none of the above.