This is dependant on what your next stage is (and whether you have storage space aplenty).
If you've finished editing you could flatten and save as your preferred file format (.jpg, .tif, etc.) - beware of over-writing original files.
Personally, I tend to save all work files as .psd and leave all the layers in place. Secondary/final files can still be produced in other formats using the 'Save as..' command. This way if I need to make any further adjustments or edits, say for printing, I still have the work file available.
There's no need to flatten just to export an image/file.
Last edited by TheFatControlleR; 08-10-13 at 12:04 PM.
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