The answer to your question in the other thread about 8 golf players and 2 matches of 4, is that you need 7 rounds - at which point all players will have played each other 3 times. A suitable schedule would be:
(4 7 6 1) (8 5 3 2)
(8 2 1 7) (5 6 3 4)
(3 2 7 6) (1 8 4 5)
(6 1 5 2) (7 3 4 8)
(2 4 8 6) (3 5 7 1)
(6 8 5 7) (4 1 2 3)
(1 3 6 8) (7 4 2 5)
This may be the best possible option for your tournament. If you mix match sizes then there are far fewer options - for example with 10 players and one 4-player match and one 6-player match per round, you would need 15 rounds of play where each player plays each other 7 times. If that's not too large for you I could post a schedule.
For 10 players you could use this:
1 5 9 3 | 2 10 6 8 7 4
2 1 10 4 | 3 6 7 9 8 5
3 2 6 5 | 4 7 8 10 9 1
4 3 7 1 | 5 8 9 6 10 2
5 4 8 2 | 1 9 10 7 6 3
6 10 7 5 | 4 8 1 9 2 3
7 6 8 1 | 5 9 2 10 3 4
8 7 9 2 | 1 10 3 6 4 5
9 8 10 3 | 2 6 4 7 5 1
10 9 6 4 | 3 7 5 8 1 2
5 1 8 10 | 7 3 4 2 6 9
1 2 9 6 | 8 4 5 3 7 10
2 3 10 7 | 9 5 1 4 8 6
3 4 6 8 | 10 1 2 5 9 7
4 5 7 9 | 6 2 3 1 10 8
where each player has 6 games in 4-player matches and 9 games in 6-player matches.
If you have only 6 players, then why not always have a 6-player match? Or are you thinking of two 3-player matches?