[Littlehelper]

^ Like luis said.
Example:

pawn Code:

new pName[MAX_PLAYER_NAME],szString[64]; // Defining pName and String
GetPlayerName(playerid,pName,sizeof(pName)); // Getting player name
format(szString,sizeof(szString),"* %s", pName); // formatting the message
SendClientMessage(playerid,-1,szString); // and here we are sending the message to player with the string we formatted

EDIT: late.