Open Question: How to attach sleepin mat to Karrimor Kodiak 30 rucksack?

Recently bought a Kodiak 30 bag and am very happy with it.
However, I am going on an expedition in 2 weeks, and have yet been able to attach my sleeping mat.

Is it possible? If so how?

Thanks
I'm not sure where these "side straps" are?

Source:
http://answers.yahoo.com/question/index?qid=20110703083841AABZiga

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