Hi Simita,
To start with, you need to have a skill matrix in place. It may be created in an Excel file where you coordinate with respective heads to provide input on the current competence level of employees. Identify who are experts, intermediates, and beginners in that matrix. Certainly, experts are critical resources, so you must retain them. Consider planning to move them to a higher band, increase their scope of work (as explained earlier), and plan training for intermediates and beginners so they can progress to the next competence level.
It is not an easy practice because we have observed that people, by the nature of their work, do not always get the chance to improve their skills, leading them to start looking for a change. Therefore, you need to put in extra effort to prepare the correct skill matrix and keep it updated.
Work on assessing the current levels of your employees, categorize them into bands, finalize timelines (e.g., by when an employee can move to the next category/band). Once decided, plan for training and development requirements and act accordingly. You must have a system in place to evaluate training effectiveness, such as timely performance evaluations, quiz contests, customer feedback, etc.
For your assistance, I am attaching a PowerPoint presentation on finalizing career paths across the organization. You may also share the same during the induction session.
Just think about what you would have expected from your management to retain you and in what way. Once you have the answer, you will be able to streamline any process.
Remember the 5 Ws and 1 H when establishing any process. :)
Best of luck.
Anup