best practice for seam sealing a new tarp?

Permatex flowable windshield silicone

another link . I have used it and it is easy,doesn’t smell,no mess,works great and is still working great.

I plan to set the tarp up as normal then apply the sealer. Is the Permatex so thin that it will run out of the seam upon application, or does it have enough tack (or tact? haha) to stay in place as it cures?

Tarptent has a good video that shows the entire process – making the sealer and application
http://www.tarptent.com/ttvideos.html#seamseal

No it will not run,it is not messy,stays where you put it,no smell,no mixing easy to use.

I have to do some sealing on my tarp pullouts. Should the sealant go on the inside or outside or both? Thanks

I went with the Permatex as Anna suggested and it worked great. Perfect consistency, at least at room temp. Easy to work with, no smell. A 1.5 ounce tube was just enough for an OWare 9×9 tarp including the custom beaks. Some of that remained in the tube and some was wiped off as waste so the total weight added was less than 1.5 ounces.

Highly recommend the Permatex.