Transphobes often say gender is like a coin, either heads or tails. They're more right than they realize.
Gender is a coin. Everybody is given one at birth, and they're given it either heads or tails. You can flip it over. You can flip it back. You can keep flipping it all you want. You can balance it on its side. You can throw it away. You can get a new one. You can take it to the zoo or museum to one of thise penny press machines. You can melt it and reform it. You can keep it melted. You could even take someone else's. You can glue fun things to it. You can paint it. You can take the paint off. You can trade them for cool shit.
Transphobes often say gender is a coin. They say this not realizing how easily coins can be changed.
And remember, cleaning or polishing your gender can reduce its value to serious collectors.