Go to Big R or some other farm and ranch supply store. Get you a little fence charger. Most chargers run off car battery. For fence use the wide nylon fencing string. It comes from binder string size clear up to 1 and 1/2 inch wide. Get you a few little rebar posts or 5 foot T-posts and some insulators and you are in business.
Tip IF you are putting livestock behind electric fence make sure they know what that fence is before you take them up into the hills. If some of your animals are aggressive, make your pen big enough that everybody has enough personnel space.