Beitzah 4:4

One may not hollow out a clay oil lamp on yom tov because doing so makes a utensil. One may not make charcoal on yom tov, nor cut a wick in two (which also makes a utensil, in the form of a second wick). Rabbi Yehuda says that one may use a flame to split a wick into two separate lights.

Beitzah 4:5

One may not break a shard of pottery or cut paper for roasting fish, nor may one rake an oven or a stove on yom tov, but one may press down on the ashes to smooth them. One may not place two barrels on either side of a fire to support a pot (because this resembles building). One may not support a pot with a wood chip nor use it as a doorstop (because the wood may only be used as fuel for cooking, otherwise it is muktzeh). One may not lead an animal using a staff on yom tov (since this is how animals are led to market) but Rabbi Elazar ben Shimon permits it.