I'd argue that you shouldn't.
I know it sounds counter-intuitive, but working your abs every day can actually cause weakness in your core. Hear me out.
This is for one reason: overuse. Overuse can not only cause injuries in your body, but it can reduce results from your exercise program, and the abs are no exception. If you did bicep curls every day, your elbow probably wouldn't feel very good. You would probably develop an inflammatory injury like tendonitis, which would set you back from continuing to exercise and increase strength.
When you work a muscle, whether you are exercising or doing a physically demanding activity in daily life, tiny tears happen in the muscles. These tears are good, as they signal your body to begin the inflammation process. This inflammation process swoops in to heal torn/damaged tissue, and the result is stronger muscles.
This inflammatory process can...