How do i tension the cam belt on my e36 318i bmw?

To do it correctly you need a tension gauge, however it is possible without. make sure your timing marks are correct,flywheel locked and camshaft locking tool in place. slacken camshaft sprocket bolt and turn clockwise to stop. fit timing belt in an anticlockwise direction starting at the crankshaft, ensure belt is taught on the non tensioned side between sprockets. turn tensioner pully anticlockwise, untill you can turn belt 90 degrees with finger and thumb pressure. tighten tensioner. tighten camshaft sproket bolt to 63nm. Remove all locking tools. turn engine 2 revolutions from the crankshaft pulley by hand. DO NOT START AT THIS STAGE!!!!!!!! refit all locking tools, if at any stage the engine locks or the tools will not refit, you have done something wrong. Go back to stage one. Check belt tension finger and thumb method, retension as required. turn again by hand. re fit all components and start. If you have whining noises the tension is too tight. Flapping or banging noises too loose. This is not a fool proof method and you have to be aware of the failings of fitting timing belts without the correct tools etc. ENGINE DAMAGE WILL OCCUR IF FITTED INCORRECTLY. A good garage should charge no more than 2.5 hours for this work to be carried out, with a warranty. Hope this helps