I was asked recently what I felt was the most important technique in scrapbooking. Aside from the obvious, which is of course taking lots of photos so you have good options to scrapbook,the most valuable technique you can learn to do that will have the largest impact on your finished scrapbook pages is to understand how to resize and crop your photos.
In each layout you should have one focal photo. That means that your eyes will naturally be drawn to that photo first on the page. Everything else is secondary. The way to create this focal point is by ensuring this photo is larger than the other ones on the page, or by having some sort of embellishment that distinguishes it from the others on the page (an arrow pointing to it, a circle around it, dots around it, large flower beside it) or by having additional matting so that it stands out. Double matting a photo is the easiest way to make it a visual "bulls-eye" on the page. (Matting simply means you are placing your photo onto cardstock and leaving a border around it so that is has a "frame" in cardstock. Double matting means that you do this twice, normally once with either white or black cardstock and then again with a complimentary color that matches either your photo or your background).
Many digital cameras come with software programs that enable you to resize your photos. There are also free programs available online. Here is one I found quickly when surfing online Dr. Pic .
Ensuring that your focal photo is larger than your other featured photos is easy when you can resize images digitally prior to printing the image. Some programs will also allow you to "stroke" or put a border around the image. This is useful since you can print your photo with your matting already on it and save yourself a step.
It is beneficial to be able to "crop" or cut your photos so that they do not include information in them that you do not want in the printed photo. Almost all photo editing software will have a cropping tool. It usually looks like scissors. You take that tool, start at one corner of your image and click down and then drag it to the kitty-corner of the image. Normally you can then see the crop or cut lines. You have the ability to put your cursor on these lines and move them until you get the image as you like and then normally you press enter and it will crop the image to the size you desired. Ideally you should have a "new" blank file open that you can then drag and drop these resized and cropped images into. That way you can print lots on one photo sheet.
Be prepared to spend some time choosing, resizing and cropping photos in your software program prior to scrapbooking. It will make the biggest difference in your finished projects.