Determine if you need to make a distinction that is crucial to identifying the subject--it is restrictive--you'll use "that".
The dog bit me. (Which dog? I'd like to avoid it.)
The dog that has bits of my trousers in its teeth bit me.
If it is some nice-to-know, but not necessary, information, use "which" in a non-restrictive phrase set off in commas.
The dog bit me. (Can you tell me more about it? Perhaps I'd like to buy one like it.)
The dog, which had been sleeping before I stepped on its tail, bit me.
INSTEAD
you can use or , otherwise, or rather than.
what can i use instead of glyerin in making tootpaste
We could use leather instead.
You Can Use Paper Bags Instead Of Plastic
In this situation, you should use "what" instead of "which."
Will, when, why, it, can
For thickening soups, stews, and gravies, you can use flour instead of cornstarch.
You could not use lightning instead of batteries.
Yes, you can use butter instead of margarine in this recipe.
Yes, you can use ghee instead of butter in this recipe.
Australians use kangaroos instead of reindeer at Christmas.