If you use 7/64 amsteel and tree huggers as your suspension attached to the hammock continuous loops via beket hitch you can use prussik loops on the amsteel to attach and adjust tarp.

If you use decent tree strap like the ones from AHE you can attach tarp via micro biners with the Dutch spider and a continuous loop. (credit to Short Round)

In either case, its best to have shock cord self adjusters and follow Derek Hanson's UHang tips on 30 degree no Hennessy tarp sag recommendations.