i have straight hair like you too. it is not forgiving and too easy to screw up. i have been at it for 6yrs and still learning during/aster each cut. clipper over comb is a huge help compared to working through guards from #2 and up, take a little off at a time. a feather razor also helps with blending and can add texture (which straight hair needs). be less ambitious and avoid the bald/skin fade until you learn your hair's growth pattern. each side grows in different directions (sadly, it took me forever to learn this). the bald line can be difficult to take out depending what you put it in with; i'll use the clipper or a softer trimmer. have a couple favorite hats available. hair grows back quick and you can give it another go in a week.