First what ya makin' it out of? whole muscle or ground? If whole muscle then use the leanest as said before like bottom, eye or top round. The thicker you cut it the tougher it's gonna be plus it takes longer.
Start out with a pre made seasoning like hicountry. That way you wont get discouraged because it will be pretty good.
You probably have the stackable dehydrator right. With them put them somewhere you don't hear the fan like your basement...it gets old real quick LOL.
Once you cut your strips measure out the cure and seasoning for the weight. Mix it up good and let it sit for atleast over night if not 24 hours. Lay the strips around each layer and leave some room in between. That will help go quicker. Usually 5-6 hours with a 1/4 strip.
Here's the latest done, Goose boob jerky last week for Christmas. This was done in a dehydrator