Timeline : 64 ticks = 0s
128 ticks = 28s

Execute :

The "lines" on the metal plate will be your references.
- Count 3 from the bottom (64 ticks) or 2 from the bottom (128 ticks) and align your crosshair with it.
- Go to the left until you are in the middle of the side of the piece of wood which is in front of you.

Left + Right click and jumpthrow! Voilà :)

Ps : here is my jumpthrow bind, which works with all type of clicks possible (left alone, right alone, and both!)
alias "+jumpthrow" "+jump;-attack; -attack2"; alias "-jumpthrow" "-jump"; bind KEY "+jumpthrow"