Sometimes an opportunity presents itself.
We were fortunate that way during the summer before my sons started K. We were out camping with friends, who had a son the same age and one older.
In the afternoon, the 4 boys were out tossing a frisbee, until it became blatantly obvious my sons were just NOT going to be able to participate like the other two. Later they pulled out a trivia board game, and my sons were confused as to why the other 5 year old couldn't read his own cards and needed multiple choice to help him answer.
The answer was easy and a great start to the discussion of differences that has taken place in bits and pieces over the past few years. Kids have different strengths, and some kids have really obvious strengths, but sometimes strengths aren't obvious. My sons were strong with reading (other strengths came up later) and the other boys were strong with frisbees.
I have never used the word 'gifted' in front of them, and don't think they have heard it elsewhere. They have been hearing 'bright' and 'fast learners' for years. It didn't take long in school for my sons to notice they were different, but they took it in stride. It hasn't been a totally smooth ride, but they are content to describe themselves as 'fast learners' and leave it at that. It has worked well for us.
I assume that there will be as many variations of what works best as there are variations in personalities. Hopefully one of the ideas strike you as 'right' and helps smooth things along. GL.