Sorry, but what you want is not possible! If you just consider the people with whom you (as an individual) will play, you will play with three others every day for four days, which makes 12 matchings; but to play with 7 players twice each, you will need 14 slots, not 12. We have previously had a similar request, and we are reasonably sure that you would need SIX days for everybody to play together at least twice. See
for a 7-day arrangement. The best you can do is to pick four of those seven days for your four rounds.