Hello and welcome to my first tutorial ever, i will keep it simple and verry easy! so all of you can follow it
First off start opening a new document You choose which size it depends on how big you want it to be
in my example i used 150x150

Second Write you're text it doesn't matther which colors or how big!
i just used in my example one color (#7200ff) and size 72 after you wrote you're text duplicate the layer by pressing control + j you will have now 2 layers

3th Now you select the bottom layer and choose a little darker color that you picked i'm using (#6328ad) darker blue and press OK, notice you won't see any diffrence!

now the 3d effect For this you duplicate the down layer around 5 times and use the moving tool by clicking 'v' and move every layer you copyed a lil above untill you become a 3d effect

Outcome!



