Reducing image quality in photoshop

I'm so sorry if this is in the memories but i've searched and I can't seem to find anything about lowering image quality in photoshop. I made a friends only banner that I want to upload to a journal but the file size is way over 250k (yea it has a lot of blending effects and such) and photobucket distorts it. How can I decrease the image size so it uploads properly? Or even better, is there another site that doesn't have image restrictions, photobucket has been my main source for quite a while and I can't seem to find another good one.
thanks for any help!
xox [J]ess