While Photoshop's most popular usage is editing photos, the software's drawing tools also allow for precise drawing and positioning. You can create lines of different widths, lengths and angle directions with the line drawing tool. Photoshop can display lines at any angle and can be specified to the 10th decimal place.
Open a new document in Photoshop. Make sure the tools pallet, info pallet, layers pallet and options pallet are viable. If not, select each one from the window menu.
Select the line shape tool from the toolbar. The line tool is located under the square shape tool. Click and hold on the square shape button and select the line tool from the fly out menu.
Hold down the shift key. Click and drag the mouse to draw a line in the document. With the shift key pressed, your line will conform to either a straight horizontal line, straight vertical line, or a 45-degree-angle line. It is recommended to draw your line horizontal and adjust the angle in the next step.
Click on the move tool in the toolbar. This is the solid black arrow at the top of the toolbar.
Click on the layer of the line you just drew in the layers pallet.
Turn on the free transform mode by choosing free transform from the edit menu.
Enter the specific angle value into the angle box on the options pallet and hit return.
You can also adjust the angles by rotating the line with the mouse. After you enter the free transform mode the mouse pointer will turn into a curved arrow. Hold the mouse and rotate the arrow to change the angle. The specific angle is displayed in the info pallet.