Hi Amal,
Its been great hearing that you have succeeded at the first level i.e making the firm debt free which is in fact very important.
Now Motivating employees is concerned so first of all you should interact with them at first level whenever it is required making them feel comfortable, though you are MD of the Firm,. You can hire some Professional and experienced HR personnel who can handle the day to day issues and provide them training sessions. Try to arrange some motivating and team building exercises.
You can also arrange some regular team meets or some get together at small level (or as per your budget), in which you being the host and handling the session which will create friendly atmosphere at the work place and the employees will be more comfortable.
Wish you Luck
Cheers!
Kalpana