How to arrange shifts?

Divide your people into seven groups. A group consists of three people, numbered as 1 to group 7. On Monday, they are on vacation: 1 group and group 7, on Tuesday: 1 group and group 2, on Wednesday: group 2 and group 3 ................... Weekend: group 6 and group 7. This will ensure that 65,438+00 people go to work two days a week and 654,300 people go to work on the other five days.