A typical crop tool lets you trim a photo in a square or rectangular shape. But sometimes it is desirable to crop at different angles. Use masking and selection tools for this type of cropping. Note that cropping removes the cropped areas of an image, so crop a photo when you are sure how you want it to look. Before you crop, make sure you have a copy of the original photo in case you need to go back to it.
Click the blue button in the upper-left corner of the Paint window. Click "Open" and select the photo you want to crop.
Click the down arrow below "Select" in the "Image" group of tools.
Click the "Rectangular selection" tool if the basic crop shape should be a square or rectangle. Click the "Free-form selection" tool if you want to make an irregular shape.
Click and drag the mouse pointer over the photo to make the basic crop shape. After making the selection, click "Invert selection" on the Paint toolbar. Click "Delete." This clears the inverted selection, removing unwanted portions of the photo as if it were cropped.
Click a shape in the "Shapes" group to shape the other angles in the crop. Paint in Windows 7 gives you a choice among several preset shapes including stars, arrows, clouds and various geometrical shapes. For an irregular shape, click the "Polygon" tool.
Draw the shape where you want to create a different crop angle. For example, draw a polygon in one corner of the photo so it appears to crop the corner at a slanted angle.
Keep the shape selected. Click "Outline" in the "Shapes" group. Click "No outline." Click "Color 2" in the "Colors" group and choose white (or whatever the background colour you want to use) as the fill colour. The shape you just created should now appear to crop the photo at a different angle.
Create more shapes to crop the photo at more angles. Make sure you remove the outline and give the shape the same colour as the background, usually white.
Review the edited photo. When Paint cleared the inverted selection earlier, it should have left blank spaces all around the image. If you want to remove these spaces, click "Select" in the "Image" group, select the area you want to preserve (leaving out the blank spaces) and click "Crop" in the same tools group.
Click the blue button again. Click "Save As." Choose a file format and save the file under a unique name.