You may employ either the level curves or the corner-point method. The graph may be sketched using the drawing tools in Excel as per the video demonstration on the multimedia page and submitted as an Excel attachment. To shade partial cells in Excel, the trick is to copy the sketch from Excel into Windows "Paint" program and do the shading there using the brush tools. Then you can copy and paste the sketch back into Excel as an image. As another option, I will also accept graphs that are sketched by hand as long as you are able to scan them into a PDF or an image file and they are neatly drawn.
Maximize: 4X1 + 5X2
Subject to:
X1 + 2X2 ≤ 10
6X1 + 6X2 ≤ 36
X1 ≤4
X1, X2 ≥0