Have a loot at this link. It discusses collimating a 127mm Mak made by Synta (ie Skywatcher, Celestron and Saxon branded Maks):
https://www.manualslib.com/manual/22...page=31#manual
The only way to properly collimate your Mak is by star testing because this also sets the scope in an position that you will be using it in which is important because of the mirror shift that these scopes have. If you attempt to collimate the scope while it is set in a horizontal position the primary mirror will not be experiencing the same forces as when the scope is pointing up.
Alex.