First,to to TeamSpeak website : http://www.teamspeak.com/ .

You will see a tab called " Downloads ",move your crossair to this tab and you'll see a few options to click,click TeamSpeak 3.

When you clicked TeamSpeak 3,A download page has been opened.
(Im thinging that most of the players uses Windows so this guide will be for Windows users.)

Click one of the client downloads,if you have 32 bit in your OS,then click 32 bit download,if you have 64 on your OS,click 64.
(OS-Opereting system.)
Before you download,you need to accept the License Agreement of teamspeak,accept them and click Submit.

After you submited,a small survey will pop-up,you can fill it or move directly to the download.
if you skiped the survey and clicked to move to download,the window backround will change and you'll need to wait a few seconds till the download windnow pops-up,save and wait till the download finish,then open the installetion.

Follow the pictures.
Spoiler

Click on Connection and then Connect.
Put the server ip : ts.sa-mp.im
And choose a nickname.(Tip:use your IG name without the underline _ )

Now you connected and have fun !
[I dont know if there this kind of guide on the forum,but i didn't find and im doing this basicly to help the people who want to use TeamSpeak.(and the one who's going to PD and need this) ]