Follow the steps below to add a tooltip to a form.
Drag a tooltip from the toolbox to the form.
Add the lines like the following to the Form1_Load event, or to a procedure called by the Form1_Load event. Be sure to change the control names to match your names.
There are multiple delay values that you can set for a Windows Forms ToolTip component. The unit of measure for all these properties is milliseconds.
You can set these values individually, or by setting the value of the AutomaticDelay property; the other delay properties are set based on the value assigned to the AutomaticDelay property.
For example, when AutomaticDelay is set to a value N, InitialDelay is set to N, ReshowDelay is set to the value of AutomaticDelay divided by five (or N/5), AutoPopDelay is set to a value that is five times the value of the AutomaticDelay property (or 5N).