You can add a walk in by simply tapping on the walk-in button at the top of the screen:

1 - Choose the number of guests

2 - You can simply seat the walk in with standard duration time or can change the duration time. The diary will choose the best available table but you can change this by clicking on the table number on the bottom left of the screen,

3 -  The Walk in will automatically populate in the diary.

Creating a walk in (speed version)

1 - Click on a the desired table (the table and timeslot will become highlighted with a blue dot)

2 - Click on 'Seat Walk-in'

3 -  The Walk in will automatically populate in the diary.