Shift Roster For 4 Employees In 24x7 Environment - XLS Download

Dear All,
I am facing a challenge in making a roster for my four members team to handle 24x7 environment. Below are the constraints.
Is there any tool by which we can do the scheduling automatically for staff. Please help.
1) No. of employees - 4
2) 24x7 environment
3) 3 shifts per day, 8 hours each
4) like to distribute equal morning, afternoon and night shifts between team members
5) like to give weekly off after 5/6 working days
6) weekly off should be consecutive
7) staff member's one weekly off should fall on weekend (i.e. Saturday and sunday) or it can be distributed as one saturday in one weekly off and sunday on another weekly off.
Please help.
Regards
Prashant

Dear Prashant,
I have prepared duty roster and attached to this post. I have done this job after 20-25 years. Hope I have done it correctly.
All the best!
Dinesh Divekar

Dear Dinesh,
Thanks for your quick response. But somehow the constraints I mentioned are not getting fulfilled the solution you have suggested.
Below are some constraints which needs to be taken care:
1) No. of employees - 4
2) 24x7 environment
3) 3 shifts per day, 8 hours each
4) like to distribute equal morning, afternoon and night shifts between team members
5) like to give weekly off after 5/6 working days
6) weekly off should be consecutive
7) staff member's one weekly off should fall on weekend (i.e. Saturday and sunday) or it can be distributed as one saturday in one weekly off and sunday on another weekly off.
Thanks once again for your response.

Dear Dinesh
I checked your roaster that is very good but we have only 3 shift no general Shift so how we can utilize 4 employees

Also, this assumes 1 day off. How do we manage to give 2 weekly offs for each person? Is it possible with 4 people working 3 shifts?