How To: Create a material parameter in Unreal Engine 4

While edit­ing a mate­r­i­al, hold ‘1’ (or search for “con­stant”) on your key­board and left click on an emp­ty space. A new con­stant will be cre­at­ed.

Now right click on it and select ‘Con­vert to para­me­ter’ option. Give the para­me­ter a mean­ing­ful name.

Now you will be able to quick­ly edit it from the mate­r­i­al instance details pan­el.