Here is a useful tool to use for illustrations, an A2 art board. As with tablets and selected pens and pencils, this is an optional thing to use, to aid your illustrations. Not only is this good for paper based illustrations but the design of this allows the use of the light box to sit on the designed ledge. This enables you to draw upright, instead of leaning over a desk or on your lap. Also, the mount at the back allows you to adjust the board to multiple angle so you do not need to worry about it, or any art work falling off.
The purchased art board came included with 4 clips, but these can also be purchased separately. However, check sizes of the board and make sure that the clips are compatible, as those are also sold in multiple sizes:
An art board can be purchased in multiple sizes, including A3 and A4, in different shapes, shades and makes. Can be easily found online, or in many art supply stores.