Making a wooden sheathe for my knife

I've always imagined this as a task impossible for my minor skills as a bushcrafter, but today on this, a fine, chilly summer evening,I thought to give it ago any who.
 It all started when i came across a video of a complete legend hoboex on YouTube, if you have not subscribed to him yet you really should. Not particularly step by step as such because he leaves things to ya own common sense, but he really illustrates how simple it can be and how effective bushcraft is  http://www.youtube.com/watch?v=kwCHCHLx984&playnext=1&videos=w3E3WXD-SyM&feature=rec-exp_fresh%2Bdiv-1f-36-HM That's the video.

 I didn't use birch bark, i did however use some random old string that i found around the house, i was going to use some cordage ide done but couldn't find any and cba to do any. Later job, i used a close hitch to start the lashing and another one to finish. I got the technique for the knots from SAS Survival Handbook, Revised Edition: For Any Climate, in Any Situation mine is the pocket one that my girlfriend got me its amazing. All things useful to know.