Guys tend to think that “shaving with the grain” means shaving either up or down. This is a misconception as each persons grain is different. Sometimes it can go sideways and sometimes it might change direction half way through.
To find it, take your index finger and run it through your beard area. If it’s prickly, it’s against the grain, if it’s smooth, it’s with the grain. Try it out, you may be surprised how your beard actually grows and you will find out how to shave with the grain in future.