11 teams in a competition playing only 8 rounds

[bdtta]

sadly I can not make this a 10 round season. So what is the best mathematical combination that will result in all teams playing the same number of matches. Team can only play one match per round and multiple byes would be allowed. Teams should only play another team more than once.

[Ian Wakeling]

I think the only reasonable way to achieve the same number of matches is to have 7 rounds of 4 matches and 1 round of 5 matches, with each team playing 6 times.  For example:

(2 11)   (3 10)   ( 4  9)   ( 5  8)   
(3  1)   (4 11)   ( 5 10)   ( 6  9)   
(4  2)   (5  1)   ( 6 11)   ( 7 10)   
(5  3)   (6  2)   ( 7  1)   ( 8 11)   
(6  4)   (7  3)   ( 8  2)   ( 9  1)   
(6  7)   (8  9)   (10 11)   ( 1  2)   
(3  4)   (5  6)   ( 7  8)   ( 9 10)   
(7  5)   (8  4)   ( 9  3)   (10  2)   (11 1)

[wbport]

You might want to consider a swiss guided round robin.  Start with a round robin schedule like this:

                 11 or 12 players
Rd    Pairings
 1:   1-12   7-6   11-2    8-5   10-3    9-4  
 2:  12-7    2-1    6-8    3-11   5-9    4-10 
 3:   2-12   8-7    1-3    9-6   11-4   10-5  
 4:  12-8    3-2    7-9    4-1    6-10   5-11 
 5:   3-12   9-8    2-4   10-7    1-5   11-6  
 6:  12-9    4-3    8-10   5-2    7-11   6-1  
 7:   4-12  10-9    3-5   11-8    2-6    1-7  
 8:  12-10   5-4    9-11   6-3    8-1    7-2  
 9:   5-12  11-10   4-6    1-9    3-7    2-8  
10:  12-11   6-5   10-1    7-4    9-2    8-3  
11:   6-12   1-11   5-7    2-10   4-8    3-9  

and choose rounds that match up as many perfect scores as possible.  Any team paired against 12 has a bye that round.  Once there is a clear leader, choose unplayed rounds at random.