I just told everyone I was Homeschooling my Son and that was that. I have gotten nothing but positive feedback and reactions. I have yet to hear anything negative after almost three years of Homeschooling, but my best advice for you is this: if you do get negative reactions, just hear what they have to say and thank them for their feedback, but remember it's only their opinion and you feel you're making the best decision for your kid. So many people stereotype and/or judge even when it isn't deserved.
I just told them when they asked how our son was doing in school, all the bad things that where happening & that we had decided to homeschool him. Some people learned about it before we started & some didn't learn about it until after we had been at it for a while. We got the typical questions about missing out on school related mile stones & all the things most people question about homeschooling. I just told them the truth about how all of that really works in the homeschool community & how what they think they know about homescooling is all stereo typing & myths. Some of them where nice & supportive others let it be known that they would never do it but said "he is your child & you have to do what you have to do". I have never had anyone just tear into me about how it was a terrible idea, but I know that a lot of the really negative stuff was said behind my back because most of them don't want to have a confrontation with me. I am known in the family as the strong willed & stubborn one that won't back down from an argument & if they had started in on me I would not give in to them even if they where right so why waist the time trying to change my mind.
I don't think I made a big announcement. Honestly,its been so long, I'm not even sure how it happened. My family knew I was leaning that way, they were supportive from the beginning. One mom, who's dd was friends with my dd mentioned somehting about them being in class together the next year and I said something like "oh, she won't be going next year, we're homeschooling". That was kind of how it happened with everyone, I think. It wasn't earth-shattering news or anything. If it's any consolation to you, I really could not tell you the details so just know that after a while, it no longer matters and you really don't even think of it. This is our normal life and I don't even notice anymore that we're doing anything out of hte ordinary.
With our situation, people asked. When we told them that we'd decided to stay together as a family and follow my husband wherever the pipeline took us, they asked what we'd do about Hayden's school and I simply told them, "I'm going to homeschool him." That was pretty much it. No one really said anything at all, except "Oh." Lol. It was surprising to me because no one in my family has ever homeschooled their children and I am used to a lot of negative comments about everything else in my life from my family, but this time, they didn't react. So, I was glad to be let off the hook. Lol
My friends and family live in Maryland and so when they found out my son isnt vaccinated they instantly say "he wont ever be able to go to school" and I just told them then that we had already decided to home school so it didnt matter. they pretty much shut up and left it at that.