All actions performed in a timer are handled in the "Tick" event.
public partial class Form1 : Form
{
Timer myTimer = new Timer();
public Form1()
{
InitializeComponent();
myTimer.Tick += myTimer_Tick; //assign the event handler named "myTimer_Tick"
}
private void myTimer_Tick(object sender, EventArgs e)
{
// Perform your actions here.
}
}