Step 1

Open your photograph or graphic in Photoshop.

Step 2

Under Image select and click on Image Size.

Step 3

To maintain the original proportions and resolution of your image when resizing, be sure that Constrain Proportions and Resample Image is checked at bottom.

The Image Size box will appear. Select Width or Height under Pixel Dimensions and type in a smaller size. 

The actual size of your image is also displayed in inches under Document Size along with the Resolution (pixels per inch). Do not reduce the size of the image by more than 50%.  Doing so will impair the resolution drastically. The image can be reduced again after sharpening.

 Click OK

Step 4

You may notice that your image has become less sharp after resizing.

Under Filter select Sharpen and click on Unsharp Mask.  This will open the Unsharp Mask box to set the degree of sharpness desired in your image.

Step 5

Check off Preview if not already checked.

With your mouse drag the slider under Amount to increase or decrease the amount of sharpness.  Generally over 100% will cause the colors to bleed together. With the preview window you will be able to see the changes in your image as you drag the slider. 

Click OK

If you wish to reduce the image dimensions further, repeat steps 2, 3, 4, and 5. 

When finished  you may save your photo as a JPEG or your graphic as a GIF.