A method for guiding a surgical cannula having a plurality of overlapping flexible tubes includes determining a desired cannula path; selecting the plurality of flexible tubes, wherein each of the flexible tubes within the plurality has a pre-formed curvature and a flexibility; determining a final overlap configuration of the plurality of flexible tubes such that a resulting curvature of the overlap configuration substantially corresponds to the desired cannula path; and determining a plurality of intermediate overlap configurations of the plurality of flexible tubes. Each of the intermediate configurations correspond to the desired cannula path.