how do you send a text message on a cell phone?

There are many ways to do so if you are using smartphone.

1 - Go in message app in your phone and then compose or write message. Choose the contact you want to send message to.

2 Long press any contact in the address book and then you will see either a new screen asking you to call or send text.

3. In call logs, long tap on any number you want to send a message to, a pop up like window will open and show you all the actions you can take. Message sending option is also supposed to be there.

There may many other ways to do so but these three are the major ones.

I depends entirely upon what kind of phone you have... This question isn't general enough.

Open siri and say 'Siri, send text to all contacts, I hate you all'

It's 2014 you should know this so figure it out yourself.

It is very easy.