Question need help on cooked grains

Hi I'm new to steer plant. I'm not new to the show ring but I'm new to showing steers. I showed heifers all the middle school and highschool but never steers. I've read a few things on using cook whole corn or barley to help put finish on steers. I've never done this so any info is welcomed. My question is I know the the calcium/phosphorus in barley isn't good with the calcium being lower than phosphorus so my question is should that be something you feed every now and again as apposed to everyday like you could the corn? And also with the barley do you want whole or rolled barley?