To show others the importance of personal development is to be involved in your own personal development program. In unstructured settings you will have opportunity to share the new things learned and accomplished. In a structured situation where co-workers or employees are being challenged, there is a chance to discuss options and recommendations based on the experiences and choices from your own research and involvement.
It is also important to encourage people to try new things. Many people are stifled by fear of the unknown and a word of support from someone they respect can provide the courage needed to attempt areas of personal development not otherwise considered.
Bringing in others that will share their development experiences is another way to help people see how important personal development can be. It can be a co-worker or a colleague from another company who agrees to share their achievements. A business coach can also be hired to come in and teach the importance of personal development along with the steps needed to help people get started. Helping people realize untapped development opportunities and challenging them to look at areas of interest will usually spark a desire to see what personal development is all about.