As the title says these are free and easy ways to improve your photos without having to fork out for expensive programs like Photoshop. I understand that there are a million things you might want to change about an image, and these are quite basic fixes and effects, but I thought I would share what I have discovered in trying to alter my images. I have used two programs to create these effects: GIMP and Perfect Effects 4.
I understand that top photographers have already framed their image perfectly and altered their camera setup to get crisp colours. For us mere mortals, the first thing I suggest you look at is the crop function (in GIMP Tools -> Transform Tools -> Crop) and Brightness-Contrast (in GIMP Colors -> Brightness-Contrast) The great thing about GIMP here is you can actually see exactly what it will look like before you make your selection. I always like to have a copy of the original image saved and open, so I can see the change. It is also worth doing incase you change your mind about the changes you have made (although there is an undo function in Edit) For most photos this is enough, as you have a beautifully framed shot and your colours look vibrant.
Other things you may wish to look at are in Filters in GIMP such as looking at sharpening an image (in GIMP Filters -> Enhance -> Sharpen) There are many effects you can use to alter your image in GIMP such as an old photo effect, lens flare etc. However, I am now going to use Perfect Effects 4 to create some Instagram type effects. First open up your image in the home screen, then change over to the effects screen once it is opened. Down the left hand side there is an array of effects that you can use, simply click on the box and it will show you what your image will look like. Then if you are happy with your image click the Add button on the right hand side bar. Your image will not be altered until you press Add. The portrait retouch is good for smoothing out skin imperfections and fixing red eye. The vintage effects have the feel of Instagram. You can layer effects by continuing to press add. The image below is using Brandon (in Vintage) and White Round (in Borders)
Hope all you Instagram fans will enjoy using these techniques to change the photos you hold on your computer. As I continue in my quest to take better photos, I'll be sure to share my tips.