To add on to Mike Brockington's answer: with textiles, a "remnant" is some amount left over:
remnant (n): 1.1. A piece of cloth left when the greater part has been used or sold.
In many ways "remnant" is just a fancy word for "scrap"; however, there is a difference in nuance. "Remnant" sounds nice, as if the remaining cloth might still be of some use. A "scrap" sounds like something you should just throw away. As with many things, this depends on context. Some people can do wonders with scraps of cloth.
We can probably sew together something with these scraps/remnants.
If you're not clear whether something is a "remnant" or a "scrap", then saying "extra cloth" is fine.
We can probably sew together something with this extra cloth.
"Leftovers" (plural noun) is normally used with food, but the adjective "leftover" can apply to any kind of extra material
We can make two pies with this dough, and some tarts with any leftover dough.
You can also use the phrasal verb "left over":
We can make two pies with this dough, and some tarts with any left over.
Side note: "Make something crafty" is not quite idiomatic. "Crafty" means clever, bordering on devious. Instead use the verb "craft":
We can probably craft something with this extra cloth.
Because "craft" is a generic term, it's usually idiomatic to be more specific, at least when it comes to simple tasks, using verbs like sew, weld, assemble, carve, construct, mold, mix, cook, and so on