Step2: open new window give width and height depends upon your requirement
Step3: select gradient tool
Step4: After selecting gradient tool in the upper side new tool is show double-click that tool
Step5: new window is open in that window gradient tool color is show.
Step6: we change the color by clicking the color .
Step7: create red and black color combination like show in the picture.(create 6 or 7 red color channel)
Step8: select the angle gradient tool.