!. Read the instruction book.
2. set up on sturdy tri-pod, 10 to 15 feet from muzzle or follow the directions recommendations.
3. Check and make sure you are shooting through the sensor area and above the sensors. Don't ask how I know this, LOL.
4.Save your readings and compare speeds, es, and SD. These will help you to pick out loads. You compare readings to groups and find the one that meets your requirements, velocity, group size , sd ,es, or all of the above.
The chrono will tell you when you are reaching the point of diminishing returns when you are increasing the powder charge. If an increase in powder only gives you a small increase in velocity you are getting close to that point.
There are many other things that a chrono can tell you about your loads when the readings are compared to the targets. You just have to devise a way to keep track of the groups vs the chrono readings. I use a old Redfield target with a large center diamond and 4 smaller ones, I also have a smaller copy of it that I number the diamonds on as I shoot my groups. It works for me.
Enjoy that new chrono.