Trunkport on Catalyst 3750 (lanbse)

[HAMZA NISAR]

Hello,

How can i make trunk port on cisco 3750 lanbase version, switch is acting on L2. whenever i try to make i received below message.. 

Regards.

[MHM Cisco World]

you do first 
switchport trunk encapsulation dot

then the 
switchport mode trunk will allow