Designer Help Please

[BobbieB]

So I figure id ask cause this has been getting on my nerve for a week

but say take this little piece. See how the effect looks great on it.

why when I try it on a 12x 12 3000 dpi paper doesn't the effect show at all?
I mean its any effect this is just the one I'm working with now.
to me even when I upload it ican barely tell somethings been done with it. but can't see the effect hardly at all and I would like it to view on a big one as good as it does on this little one.