How can I make myself shoot more deliberately with a digital camera?

You need discipline and a goal.

Most digital camera users take hundreds of shots without thinking much. Tons of shots are almost the same and most are unmemorable. I also know pros who shoot thousands of photos per day. That's a huge number! The great thing about digital photography which I tell my students on the first day of classes is that experimentation is free. However, shooting without thinking does not teach anything, its more like playing the lottery. You're going to eventually get a few good shots but you wont be able to repeat it or control it.

Most people are surprised how few photos I take and I actually plan to take fewer because I gave myself a goal of not shooting the ones that would get culled. I used delete 9 our of every 10 photos I shot and have been striving to reduce that number of trying to recognize in advance photos without merit. It's tough but I am down to deleting 7 out of 8 now. The strategy to do this takes discipline:

1. Previsualize
2. Position carefully
3. Inspect every edge and the content of the frame.
4. Search for highlights and shadows, decide where to meter.
5. Set exposure parameters depending on the mode.
6. Don't forget White-Balance. Take a reading if using custom. Even with RAW for a better preview.
7. Watch motion in your frame and focus.
8. Shoot and review.
9. Analyze what could have been better.
10. Repeat as needed.

Obviously this needs to be adjusted for different situations and things with rapid motion generally take more shots. Even using burst mode you must anticipate motion not to run out of buffer before the height of the action.