Most cameras use landscape orientation by default; you might physically rotate the camera to shoot a portrait, but when you view the image, it still displays horizontally on the camera screen. This forces the all-too-common, head-tilt preview as you scan through your photos. Even if you intentionally shoot a photo in landscape mode, you might later need a version in portrait orientation. Either way, you have options.
Rotate the Photo, Not Yourself
Most photos display horizontally on your computer monitor when you import them from the camera. Rather than reverting to an elaborate yoga pose to view the images, grab the nearest piece of graphics-editing software and correct the orientation. Almost all editors -- from bare-bones Paint to the comprehensive Photoshop program -- have a rotation tool. Look for this feature on the main toolbar or the Image or Edit drop-down menu and choose one of the 90-degree rotation options. Select "Left," "Counterclockwise" or "CCW" to move the right edge of the photo to the top of the screen; choose "Right," "Clockwise" or "CC" to rotate the left edge to the top.
Crop Out the Boring Stuff
If the captured image is correctly displayed in landscape orientation, but you need a vertical orientation, rotating won't fix your problem. Instead, crop the image to remove unnecessary elements on the left and right of the subject by drawing a selection marquee and then selecting the "Crop" option. Basic editors like Paint don't offer much guidance with the task, but in programs such as Photoshop, you specify a ratio of width to height to ensure your selection area matches the intended output. A common portrait mode ratio is 1-to-1.33 for width to height.
Let the Printer Do the Work
Often, when you print a landscape photo, it shrinks to fit the printer's default portrait orientation rather than printing in landscape mode and filling the page. Many graphic editors and viewers automatically adjust the printout for you, but some force you to manually select it. Look for a "Layout" or "Orientation" option in the print dialog and select either "Landscape" or "Horizontal." From the printer's perspective, the image then rotates vertically, so the landscape photo fits the entire page.
Expand Your Options as You Shoot
A low-resolution, single-orientation photo limits you when it comes to editing, because cropping out the unimportant elements reduces the size further. If you're not sure how you'll ultimately use a photo, shoot it in high resolution and in both portrait and landscape orientations. Doing so ensures you have the correct orientation for your display medium and gives you the option to significantly crop the photo without reducing it to thumbnail size.