I have a lot of people come in and ask for suggestions for getting images ready to print, so I thought I would address this. If you are going to print images you may was well get the best quality.
The first thing to remember is that unless you balanced your monitor more than likely the image on your monitor will not match the final output. If you are having me print your images I will correct them for you at no charge so they look the best when printed. If you adjust the color or density do so using a layer so that when I get the image any changes that you made are not permanent, this saves blowing out highlights that cannot be recovered or correcting the color so it is beyond fixing. If you like I can also provide you with a target to check by eye how close your monitor is. If you want to make sure that your monitor is 100% correct the best thing to do is to buy a calibration tool and use that.
Cropping – Make sure that when you crop you do not crop too close to a subject. Remember you are more than likely going to frame the print and having the head at the edge of the print is going to be a problem when framed.
Adding signatures – Like above if you are going to frame the print make sure that you leave space around your signature. You should have your signature at least 1 inch from the bottom or the sides. 1.5″ is better.
Black & White prints & color signatures – if you are having a print done in black & white make your signature black & white. It looks horrible when you have a print completely B&W and this color signature in the bottom.
Density – even if you have a balanced monitor your prints will generally be displayed in a dark room, so make sure that you do not have your prints so dark that when hung on the wall they are all black. Making your prints a little lighter than you like them on your monitor will get you a good print to hang.
Media – it makes a HUGE difference what you print your images on. Some pictures just do not look good on gloss when other look great on gloss. Some images should not be printed on canvas, other images pop on canvas.
Image size – size is not everything but it does play a huge part in getting a good print. You should be cropping your images to print size @ 300DPI. If your image is sized to a 1″x2″ at 72 DPI you will not be able to get a 20×24 from that.