Getting my puppy`s attention in all situations?

I have a 3 month old puppy. Last week, I looked up several instructional videos online, and was able to teach him to sit, come, and lie down. He will do these behaviors on cue 90% of the time. However, if he is distracted, such as when he is in a new environment or when company comes over, he will not obey the cues. I am mostly concerned about the come command, as I will often need to use it for his own safety. How can I make him learn to come EVERY time, and keep focused on that? One idea I had is to use an extra tasty treat, like cheese, and do several repetitions of it every day (I used kibble to train him). Does anyone have any advice to spare on this issue? Cheers!