This is where you have to be really careful. It is very easy to over tighten these adapters, just as it is easy to not tighten them enough. You need to make sure you have a solid, but releasable connection. When you are attaching the T-Ring adapter to your camera, and the camera to the telescope, your CCD is basically unprotected. This is another reason to set up indoors in a clean environment rather than fumbling with the connections in the dark.
Once everything is connected, you simply use the telescope as a manual lens. In my case, the Meade ETX 70 becomes a 1250mm, f/10 telephoto lens. Keep in mind that the eyepiece you would normally attach to your telescope also enlarges the image, so don’t expect the same magnification when using the telescope as a lens. You won't necessarily end up with a frame-filling image of the moon in all its glory.
At this point, you will use the telescope’s focusing control until you get a nice crisp image, and then use your camera as you normally would. The nice thing about using a DLSR is you can experiment with bracketing your exposures to ensure you get one you like. One mistake I made was viewing the images on the LCD and accepting the exposures based on that limited example. Remember, when you are outside at night, your LCD will look brighter than it really is, so many of my attempts resulted in under-exposed photos.
A few final thoughts to keep in mind if you want to try this. I experimented with the full moon, but after thinking about it, I realized I would have gotten better results if I had attempted this during a different phase because the angle of the sun’s light would have highlighted the peaks and valleys, giving the craters and features more contrast. I’m also kicking myself for missing out on the chance to capture the recent harvest moon. Remember, the moon is at a different distance from the earth during different times of the year, and appears larger or smaller depending on when you view it. Plan your astrophotography experiments accordingly, and have fun!