how do you create of six values that does not represent a linear relation. All the y-values must increase in value as x increase in value?

easy - just make sure the changes in y are not a multiple of the changes in x.

x: 0 1 2 3 4 5
y: 1 3 -99 20 31 22

In fact, almost any six pairs you choose will likely not be a linear relationship.