Currently Being ModeratedFeb 15, 2012 8:14 PM (in response to danieliowa)
Connect your Device to Computer. Select your iDevice under "Devices" on the left Pane.
On the right Pane, under SUMMARY tab, make sure MANUALLY MANAGE MUSIC AND VIDEO box is checked. Then click the APPLY button on the lower right Window.
Now you can drag the songs over to your device.
Repeat above steps for other iDevices.