I've never found any other way other than with a tightener. Sometimes, even with a tightener, it will be kid of baggy in certain areas. For example, the top will be tight, but the bottom wires are loose, because there is a slight curve to the land. When that happens, I use one of those fence-pliers tools and make crimps in the loose wires to make them the same tension as the ones that are tight.
Take those, stack on top of each other and drill holes through both of them.
Get some long bolts and nuts.
Lay one board on one side lean or lay fence over it and then lean/lay other board over fence lining up holes. Run bolts through and tighten down. Put chain around board and fasten so it makes loop and then use lawn mower or truck to pull it tight by looping another chain through the loop and attaching to tractor/mower/truck hitch. Fasten off.
By woven wire, do you mean chain link? If it is chain link , make sure the ends are even, slide a slim pipe board etc through the links, then evenly space out some rope etc, every 2' or so, and then pull to make it even. Do not overstretch it, heat and cold will make the wire contract and expand.
Do you have a lawn tractor? That's what my neighbor said he used to pull cattle fencing tight. Honestly, IMHO, I would start making a real fence with posts and wood. You can start with one panel on the outside of your electric fence, and add a panel at a time over a few years--if the $ is too much--then take down OR leave up the inside electric. You put the horizontal planks on the INSIDE of the posts.