Here is one way to make a cone from flat stock. I used aluminum sheet coil but you could use paper or any flat material. You can find cone calculators online, I used this particular cone calculator ... ...
by Justine Hovey
by Navin Khambhala # crazyNK
by giddyupworkshop
by Akshay arts
by WoolyWondersCrochet
by The Creativix
by craftzone4u