Don't be annoying when you post

You listen a little bit first.

You post only to appropriate newsgroups. (On-topic)

(e.g. comp.lang.c does not want questions about vacuum cleaners)

You post something that contributes something new to the discussion, and is
something that people will generally want to read. (Intending to advertise? Then
you had better read: Spam)

It is easy to post something that almost no one is interested in reading, and this will only serve to annoy everyone for wasting their time. If you want to tell someone "congratulations" or "I agree" then say it with e-mail.

You can post to ask for help on something in particular.

But you should look around the Internet first. Someone may have already asked and answered the question. Not only will you cut down on unnecessary questions, you will get what you want faster. See How to search article text

If you want to make a test post, then use a local group reserved specifically for testing, or the newsgroup alt.test.