Hi Jack, apologies for the delay.
There are 2 types of picture tours on the site - 'main' and 'user created'.
The 'main' ones are just a way of categorising pictures and can be found here: http://www.picturesofengland.com/England/tours
You can add one of your pictures to these main tours/categories by clicking the edit link on one of your photos when logged in.
The other type of picture tour (such as the Jurassic Coast one you refer to) is a 'user created' one. Unfortunately only the person who creates the tour can add pictures to it, however as I created the Jurassic coast one I have added your West Bay photo and Tori's Durdle Door photo to the tour.
Hope that helps,