I have Princess Diana too and i planted mine in a border where it grows up the surrounding shrubs.
If you want yours to climb the arbour it'll need either a plant to cling to (like a rose growing up there too) or you'll have to attach some plastic coated wire to it (the arbour) because the plants tendrils need thin/fine things to cling to.

Thank you Louise1. I have a rose bush and a jasmin on opposite sides of the arbour so will probably plant it near the rose as you advised. Clematis are my favorite flowers and i can't have enough of them but don't have the ideal space for them to climb. The fences on both sides of my garden are only 4 feet high and the shrubs are still getting established. Hence the arbour will have to do for now.