Those are all great approaches. To excercise them, go to p. 40 in your Arban. Play the excercises beginning with ascending slurs in 4ths slowly, at about mm quarter=72. Think of smooth connection, blowing up to the upper note as (toe-hoh), following the dynamic indicated. No stronger than mf, though. Then the 6ths, in quarter notes. Same idea.
What are you waiting for? Get busy!
