First we need to ask you the question of what exactly you are clipping. Are you clipping steers or heifers? and are you clipping purebreds or clubbies! Believe it or not there is a big difference. with a heifer, the 5/8 blade works great, with steers, usually you want to block out the shoulders and front end, but if your afraid of that, I would tell you to use the 3/4 blade to begin with on steers. When you are using the guards, you want to watch how far back on the shoulder you go and and how far down. You really need to clip the forearm and point of shoulder to gradually go up into the shoulder. With heifers I have seen people take the 5/8 blade from the base of the neck forward and a 3/4 on the shoulders. If you do that, take your blending blade and make sure you blend in the line that you are going to create. If you aren't the greatest, I would advise using a 3/4 all over then using your blending blade from there. Watch going at it with a blocking blade because if you arent super experienced with it, it is the gauging king. I personally using the 5/8 blade and blocking blade, but I have done it awhile and clip cattle every weekend and have became comfortable with it. That 5/8 blade and 3/4 blade is like clipping with training wheels and Everyone loves it. your blending blade can be your best friend. If you are clipping purebreds I highly highly advise it because a lot of purebreds depending on the breed dont have a lot of yak and the hair can be nappy or fine, and that 5/8 blade cleans it up like a charm! If you are doing steers, I would say use the 3/4 blade. You want to keep that thicker fronted steer and try not to make him feminine. I advise trying to learn how to block the shoulders out. With their winter coat, nows the time to try it on some old cows that are halter broke. But I would use the 3/4 blade if you are worried and then use a blocking or blending after that. If you would happen to really really nick one, you can always put on the 5/8 and continue. Just remember if you nick one, please dont take off too much trying to fix it. clip the rest of the cow then come back if you need too. A lot of people make a mistake of trying to fix a nick and then ruining that whole area. My last advice is, A) Go around and find some good fitters and just watch them clip at these shows. I was at the ohio beef expo and saw Guyer clipping an underline. I stood there for a half hour and learned more about clipping an underline in 30 minutes than i had in 10 years. I was standing there like man that looks good, I would be done, there he is taking off micrometers of hair. Heck i bet 10 strokes he only took off one hair (exaggeration but you get the point). B) Purchase DVDS. I rewatch my clipping DVDS probaly once a month atleast. I ordered the Guyer ones from Purina and I have old ones from Steirwalt. Also take advantage of these Stock Show U Clinics. Everybody clips different and there are alot of people that are great. Watch everybody and learn what works best for you. But definitelyy pick up the 3/4 blade and the 5/8 blade. And you only get better if you practice A LOT. I hope I helped