Technically speaking, since your speakers have internal crossovers, they don't require bi-amping. The very simplest thing to do is to wire the Low Frequency and High Frequency terminals together (LF- to HF-, LF+ to HF+).

[EDIT: This is usually true, but not this time -- these speakers don't contain ALL of the things usually found in a crossover. Moral: Read the manual, and take anything some yahoo like me says on the internet with a grain of salt!]

However, if you've already got the M200s to spare, you can drive LF with one and HF with the other. Just put a Y on the 950 output and run the same signal to the input of each M200. This is "passive bi-amping" since you retain the passive crossover in the speaker.

You may want to consider trying "active bi-amping," which is the same except the speaker crossovers are removed, and an electronic crossover placed between the 950 and the M200s.

My experience -- this year, I altered my speakers to try passive bi-amping, then altered them again to try active bi-amping. I used the two spare channels of my 7100 amp. Passive bi-amping was almost identical to mono-amping for me, and I doubt I could tell the difference in any realistic listening scenario. Active bi-amping, on the other hand, made a dramatic difference; well worth the effort. Of course, your mileage and opinions may vary.