I've been working in mobile development for about seven years now and deploying to iOS devices has always been the bane of my existence. One of the most annoying elements is waiting on a 20 minute build - only to hit a "build failed" error (at the end of that 20 minute build) in xcode because something isn't properly configured - typically the provisioning profile.
I'm going to answer this question because I believe I've finally found a fool-proof way of deploying to iOS that circumvents the need to be an admin on your Mac or, as in my case, even if you are an admin on your Mac - because you don't have the credentials of the first person who happened to set up your machine.
What can happen is you'll import the certificate/provisioning-profile, finish your build and then be presented with a dialog like this:
In my case - more often than not - the Mac I'm using will not accept my credentials - even though I'm an admin on this system.