There are methods stated on the earlier replies to send Bitcoin such as hardware wallet, QR code scanning etc. But at the end of the day it needs to be broadcasted online for the blocks to confirm. So there is no way to complete a transaction without using the internet.
It is worth noting that sending Bitcoin offline is way more complex than sending Bitcoin through internet. Although these method increase the security I believe it has its own set of risks and limitation.
Methods of sending Bitcoin offline as stated on earlier replies
- hardware wallet
- paper wallets
- QR code transaction
- Air gapped device
- infrared