You could try searching some of the tube sites for "handjob compilations".....
But, like most things sexual......theres no end of variations in handjob/blowjob techniques
See how he reacts when you suck, cup, stroke or lick his balls or touch his ass??
Would a prostate massage offend him .... or send him into orbit
You could always ask him to masturbate in front of you and observe his methods
Why don't you just ask him what he likes and have fun taking it from there.....