multiple tabs referencing sections of model in draftsight

Hi, I am new to CAD, using Draftsight.I am editing a drawing that has 16 tabs, but all the pages are viewable in the model. I have added another 3 pages of drawings to the model, and have added 3 additional tabs to the layouts, but do not know how to get the new pages on the model to relate to the new tabs on the layout Anyone able to help?

Thanks

James