Poly as underlayment.

I figured that might get your attention, but click the safety back on because I'm talking about temporary underlayment.. 

  I need to see through this temporary underlayment to measure from the existing sheathing seams to locate and install new framing for 24" overhangs etc..  Once the new framing is installed over the poly, the underlayment will be removed and new sheathing and roofing installed over the framing.

Or does anyone have a better solution?  How would you secure the poly for a month in a windy location?  The disadvantage I see is how slippery poly could become if wet on 3:12, but did find something called Dura Skrim 10mil string reinforced clear UV stabilized plastic sheeting that's strong and textured with the strings..

Thanks

Thanks.  Im using a bill board tarp or two because I can mark all the trusses.. 

Will have to use a SA anyway.  But before I can start I need to repair a load bearing wall..

To use Dura Skrim 10mil string reinforced clear UV stabilized plastic sheeting as temporary underlayment, secure it with roofing nails or staples and weigh it down with sandbags in windy conditions. Its clear nature allows you to see through to the existing sheathing seams for precise measurement and new framing installation. Ensure safety by using non-slip shoes and possibly safety harnesses due to its potential slipperiness when wet. 

Ive figured out a way of marking each truss to locate them after covered with underlayment.

What type of underlayment would be best for a couple of months of windy exposure since Im working alone?  I also want to be able to patch the underlayment with roofing cement so figured 30 lb felt.  Heard good things about Deck Armor and like the lines, which is also permeable but wasnt sure if roofing cement is compatable.