The Ethics of Ethics?

So, I am left wondering what to do when your ethics (or maybe personal philosophies is the better word) differ from those around you.

Not that those you are around are doing anything illegal or immoral.  Just, different.

What is the correct way to express those differences?  Should you just go out doing what you do best, and allow others to note (or not note) the differences?  Should you be more vocal about what your views are, so that at least others are fully aware?  When, if ever should you try to promote your viewpoint(s)?

For some categories these  decisions have been generally decided.  For vegetarians, you look for ways to alter a meal, or can prepare a separate proportion (for vegans or lactose intolerant, you can just toss out my entire repertoire) .   For religious differences there have been great efforts over time to try and build bridges (and regrettably many wars in attempt to just wipe out the differing religions).

But what about the smaller more personal viewpoints or approaches? 

Just wondering