PP and saving for printing?

Is there some sort of method or accecpted guidlines for preparing a digital file for printing? I've pretty much got a workflow down for saving for the web, but I really don't have a clue as to any best practice guidelines for preparing an output file for printing.

I currently archive my (keeper) RAW files, and for any file I edit I save a full res jpeg for printing and a web res/sharpened jpeg. Is there any special editing that I should do to the full res jpeg to prepare it for printing? I save in sRGB and all that, but I'm just wondering if anyone has any tips. Compared to a web file should I be using more or less sharpening, noise reduction, contrast, etc.? How does sharpening at full resolution translate to an 8x12 vs. a 4x6?

I've generally been happy with my prints so far, but I used to be happy with my p&s snapshots too. I just want to make sure that I'm not making some mistake that will make me look back a couple years from now and wonder what I was thinking.

save at highest quality, and 300 dpi for print. Most of the shots I take, I print. I generally use a USM of 150,.3,0 or up to 200, .3, 0. Seems to do the trick. I don't do noise reduction..I use a middle setting on the noise reduction my printer has (Epson R1800). Generally my shots aren't very noisy, though. Contrast depends on the shot. I don't do any less to a shot that I know won't be printed bigger than 4x6. I do my best on all of them. It's just insurance.

Use of NIk sharp pro takes this decision auto.

Almost everything I print is 27.7x40 cm / 11.5x16 in. (A3 with 1 cm. border). I uprez to 360 ppi, the native dpi of Epson printers, since my resampling routine is much better than the driver's. ( I also don't reccomend letting the driver do any sharpening or noise reduction or color management. The only thing I let the driver do is bit depth reduction, i.e., I send the file to it in 16 bits so that the on-the-fly conversion to the printer/paper color space is done in 16.) My working space is Chrome 2000 which is just slightly larger than my printer/paper space. I sharpen before uprezzing and then again after. Because ink drops spread - how much depends primarily on the paper, but also on the printer's drop size and shape - a print will be less sharp than the monitor display. Therefore, you should sharpen more for printing, until it looks slightly oversharpened at 100%. If you are printing from a program that allows soft proofing it is probably worthwhile using it and then adjusting contrast and saturation accordingly.

Thanks for the insights. I typically use a jpeg compression of 8-9 progressive. Is that adequate, or should I use less compression?

For printing, the more data the better. Think of it this way. If the original file for the photo is around 23 megabytes (23,000,000 bytes) in TIFF and you scale it down to JPEG. Your scaled down file ends up to be around 1.9 megabytes (1,900,000). Thats 21.1 megabytes (21,100,000 bytes) worth of information in the photo gone. Lose the compression.