Here are some ways to describe:
1. the style, or way, of doing something: the manner
2. the method of doing something
We can use:
He spoke loudly.
He nervously opened the letter.
He spoke in a loud voice.
He ran with difficulty.
The car approached at great speed.
We kept warm by jumping up and down.
You know when to change gear by listening to the engine.
We use by:
We traveled by air.
I prefer traveling by boat.
We sent the message by fax.
You can cross the road by the bridge.
We decided to go on foot.
She cut the bread with a knife. (She used a knife.)
You can't get in without a key. (You need a key.)
These houses are made with cement. (and other things)
This wallet is made of leather. (and nothing else)
Paper is made from wood. (We change the wood.)
Aluminum is extracted by electricity. (by for processes)
The message was sent by John.
(= John sent the message.)
The message was sent with John.
( = John carried the message; somebody else sent it.)
NOTICE: The message was sent with John. That way, it arrived on Saturday.