What steps can pilots take to mitigate the risk of controlled flight into terrain (CFIT)?
There are a few things you can do to help mitigate it. 

Get An Instrument Rating: Some CFIT accidents happen during a nasty mix of mountain flying, scud running and an inevitable flight into IMC, which ends with hitting the side of a mountain, an instrument rating here can be a truly valuable thing in these situations. 

Plan Your Routes and Minimums Carefully: This takes place in the preflight and you should always check your charts for minimum altitudes as well as man made obstructions that may be in your flight path. Once you have your minimum altitude selected, stick to it. If weather does not permit that altitude either alter your course or scrub the flight. There is some good info from AOPA on it here.



Synthetic Vision: Apps like ForeFlight are quickly becoming common place in aviation as are glass cockpits, and these have proven invaluable in terms of terrain awareness and avoidance as many of them now include synthetic vision with terrain maps. Good preflighting is still key and you should always inform your self of all potential terrain before a flight, while technology can aid in avoidance you should always have a backup plan. 

Avoid The Mountains: This is sometimes not an option but if you as the PIC feel uncomfortable you should always choose a route around terrain if possible. 

Practice Mountain Flying: Just as you would with any other aspect of aviation you can always get an instructor and practice mountain flying. The FAA has some tips here but mountain flying carries its own risks and unique cases that you should be ready for. Mountains can have turbulent airflow and you should make an effort to understand how wind flows over them, you can find a discussion on it here. 

 

Get a FIS-B Weather Receiver: As mentioned above winds can be important when flying. It's worth it to have an FIS-B weather in receiver so that you always have the most up to date information.