hyacinth, has a good system, on her website, training young birds, ours used to fly a maximum of 20 mins & the bloke down the road an hour, we have now started the flagging system, which has worked 100% for us so far, its a bit of hard work to start(running up & down garden with flag on pole isnt it westy ) but well worth it, me & my son have noticed its a winner for us!
now as soon as they see the flag, they fly & fly. but as soon asits down, and out of site, the corn tin rattles & they are in.
good luck.