Working color spaces and print color spaces are distinct, separate things. Generally speaking, you never want to directly apply a print profile to an image. The purpose of ICM is to utilize ICC profiles to describe what needs to be done when moving content from one device to another. You NEED to keep your photos tagged with an RGB ICC profile that properly describes the image in the RGB space, and you NEED to select an additional ICC profile that properly describes the capabilities of the printer. The ICM engine will then (normally) figure out how to adjust colors...according to your selected rendering intent...from the RGB space to the printer space.

To demonstrate my workflow, I generally do the following:

1. Do primary processing in the largest RGB color space I can (normally ProPhotoRGB).
2. Create a copy of my primary working image, and convert to an RGB color space that as closely matches the gamut of the print as possible.
   • This may be sRGB if the paper is a limiting factor.
   • This is often AdobeRGB, as my Canon PIXMA Pro9500 II supports a gamut that largely covers the AdobeRGB gamut
3. Manually scale the print copy to the exact dimensions necessary to accommodate my print.
   • If printing at 300ppi @ 19x13", I would scale and crop the image to 5700x3900 pixels.
   • Perform any print sharpening necessary to bring out desired detail
   • Preview at "print size" using the zoom tool (make sure you configure Photoshop with an accurate screen PPI...the Apple CinemaDisplay 30" has a 103ppi resolution)
4. Soft-proof the print in Photoshop, by selecting the appropriate printer ICC profile that matches the printer AND paper I intend to use
   • First and most importantly, I try to adjust black and white point to lie within the limits of the print gamut
   • If necessary, more so when using Relative Colorimetric rendering intent than Perceptual rendering intent, fix out-of-gamut color (search the web for a variety of techniques for this)
5. Print, leaving the image profile what I selected in step 2, and selecting the same ICC print profile as in step 4

I want to stress at least checking the white and black points when in soft-proofing mode. Using a Perceptual rendering intent when printing will usually do a pretty good job, but its easy to lose a lot of tonality in the shades and sometimes in the highlights if you don't adjust them for the specific printer and paper you intend to print on. Adjusting them in soft-proofing mode ahead of time helps maximize tonality for print. Generally speaking, you don't need to worry about out of gamut colors if you convert to an RGB space that closely matches the printer space. With modern Epson printers, that is probably closer to AdobeRGB than sRGB. If you prefer to use Colorimetric Rendering intent, then you might want to learn some techniques to fix out of gamut colors before printing, to maximize your control over color quality and minimize posterization.

Finally, once you have tuned the print copy for the specific paper and printer, save it with all your adjustments. You should be able to print from it as many times as you need with predictable results. If you ever need to print on a different printer, paper, and paper size, you should redo steps 1-4 above for each one, and save a separate copy off for each.