peasy,,,, LOL looks like mega fun Merit mate, you installed any, what's the product brand name, spec. etc...
Guess the mark out would be walk in the room chuck one over your shoulder and start from there, skirts would have to be off can you imagine scribing/marking one of them in to a wall!
That's how I mark out most mate! It would do your nut in fitting that all day, actually looks pretty good tho! If you like weird lizard shaped floors