I'm still training my pup mate,
found it best to start with a toy in the house somewhere where she can't get away from you, hallway maybe, throw the toy( not to far) and when she picks up the toy call her back ( work on re-call first) when she brings it back make a big fuss of her and give her a treat, do it a couple of times and stop. Mine picked this up easy with practice. Next take her in the garden and do the same lengthening the distance ( don't over do it keep it short and fun).
I've been using a rabbit skin dummy now and she's taken to it well, I throw the dummy and she retrieves it