First, I would like to point out that, the framerate has an affect on your trick. You may have to change to camera angle to the right or left depending on the graphics mode you are playing the game in.

When you are in the Engine block room, you have to run all the way to the end on the right.

To to the skip you have to hold A and R at the same time and then strafe to the left.

Then you must jump get on top. You need a good angle to do this.

I hope my explanation makes sense, good luck!