Welcome to GameBoomers!
Since I haven't played this one, I compared about six different walkthroughs, and this seems to be the best description of what to do. I hope it helps (since it's fairly complicated, I think it might be a good idea to print it out so you'll have it right beside you as you work): SPOILER
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
Trick for dagger puzzle :
1) Turn the face so it is "straight", then (mentally, or on paper) number the tiles, starting at the TOP (#1) going around clockwis(#4 will be on the BOTTOM).
2) Look at the first tile down from the top on the RIGHT side(#2), if it is OK leave it alone, if not - turn the BOTTOM one (#4) clockwise, a click at a time, until it (#2) is lined up in the pattern. BUT - every time you turn the bottom tile one click, the face moves - so you have to turn him back (counter-clockwise) to "straight" - this keeps the tiles in their places after you have moved them.
3) Check the TOP tile (#1), if it needs adjusting, move the one to the RIGHT of the bottom (#3) as in Step # 2, being sure to keep the face "straight" so you don't lose the tiles you have corrected.
4) Check the tile to the LEFT of the top one(#6), use the tile (#2) to the RIGHT of the TOP to make corrections.
5)Keep this up, moving the tiles in order, ie: #4 fixes #2, #3 fixes #1, #2 fixes #6, #1 fixes #5, and #6 fixes #4 (the BOTTOM tile), until all the pattern is correct. Then hit the knob.