my version to add to your confusion
copy your website link 1st & come to YT - go to edit siggy -
then type in what you want people to see - & choose your font style, color etc - then :
HIGHLIGHT THAT TEXT you typed -
click the blue WORLD icon
& PASTE Your website link in the little pop up window - it will start with 'http" and press ok.
Click PREVIEW SIGGY and it should have your link in whatever text you typed.