Do this:
AwareApp.startProcess ('ManualInvoice_ChooseDealer', { newTab: true, id: 'The id you will use to close tab' });
You can also optionally set label of the tab, icon and margins:
{
newTab: true,
id: '....',
imageCls: 'icon class',
margins {
top: 10,
bottom: 20,
left: 30,
right: 40
}
}