Before switching to the 2013 look and feel, you can still edit pages in the browser as you did before. SPD 2013 doesn't have design view so even after getting the 2013 look and feel, you still won't have the SPD wysiwyg editor (only the browser ui).
You can still use design view by opening the sites in SPD2010 if that's what you're looking for. Look for "How To Open A 2013 Site In Sharepoint Designer 2010 " in this blog ».