Sounds like you need 'Ride Like a Pro' by Jerry Palladino... it's very easy to download. Check it out on Youtube, it's slow speed skills training. It's basically learning to properly balance the throttle with the rear brake and the clutch and turning your head and eyes. Then practice in a car park.
Excelent video well recommend, also consider a few days on Mr Paveys off road centre if you want to really develop skills with no risk to your own bike.
And maybe next time take a lowered suspension model for test, on the highest seat settings or the Normal Seat if feet down confidence is an issue.
While practicing slow turns in car parks I have found the GS really needs a good few revs and rear brake while the clutch is managed in the friction zone otherwise it's weight can quickly fold the front wheel on really tight circles while sat down. It's also much easier stood up on the foot pegs in slow tight manoeuvres, to counter balance any weight shifts.
Above all look where you want to go, as Jerry Palladino says "You look Down, you Go Down".



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