Ševčík indicates that we can play this variation either loudly at the frog or softly in the middle of the bow.
When playing at the frog, use a hand and finger action supported by a ‘soft’ wrist joint and a passive balancing movement in the upper arm. Ševčík suggests that you start up bow for the loud spiccato stroke at the frog. A fluid control of the collé action will help with this stroke. Practice Kreutzer Study No.13 with a collé stroke right at the heel to help develop fluency. You can also practice this variation at the frog of the bow starting down bow.
When playing in the middle of the bow you can get more resonance by substituting the forearm for the hand in the spiccato action. Using the forearm allows for a longer stroke closer to the string which creates a more ringing sound. When playing over two strings you can use a pivot string cross but when crossing three strings the upper arm helps with the larger string crossing.
In bars 11, 13 and 15 Ševčík changes the direction of the string crossing action so the bow pattern remains the same but is reversed.
Make sure the left fingers are always securely in place before the bow starts by practising double stops to begin with or by ‘Note ahead’.
Do take the time to practice the bowing variants. In the 1st variant Ševčík adds a slur which changes the pattern.