After you do this for a while add the body movement to flatten the blade on the body as you avoid getting hurt and after a while adding a hand focusing on giving no support to the attacker so he will not have a change of plans and on your own movement. Avoid trying to succeed or make a grab and allow it to come to you and than you will see the available opening instead or trying to make one. Think of it as one step to avoid but to close or escape and keep walking.
The attacker should strike the walker in the face or anywhere that shows the emotion or intent with his free hand if the walker tries to overpower and wrestle the knife away and thus helping him see the pig picture and relax.
I suggest you start with rolling slowly on each other as you hold the knife to relax each other and than if you can walk slowly on each others body to bring awareness and relaxation before the above written drills are done.
And remember that you have a second chance only if you live though the first.