QUOTE
Depends on what program you use
it depends quite heavily on which program you use.
all programs have diff. ways they structure their layer pallete options. Also, make sure that you have the pallete up for your layers to show.
two of the most used programs are below.
adobe: blending options
psp: layer opacity
if your layer pallete isnt showing let me know which program you use and ill let you know how to bring it up.
dont worry. sometimes things seem more difficult than they actually are.