In whatever way it seems better to you to please the Lord God and to follow [in his] footstep and his poverty, do it with the blessing of the Lord God and my obedience.Franciscans love to puzzle over the odd singular, "footstep." For me, I think of it as the Cross. For when the almighty, eternal, spiritual God passes over and makes an impression on time and space and human life, that impression is the crucified Christ. That is, a burning love that is literally dying to save each and every one of us from the misery we have brought upon ourselves and each other because of our selfishness and sin.
I imagine the Franciscan vocation as a resolution to put our feet into the footstep of the Cross, trying to walk within and according to the burning love of the Crucified.