writing multiple bytes to the serial port / Arduino

I'm starting to play with Arduino (to control DMX) and most of the examples just write 1 byte to the Arduino: I'd like to send messages with 2 bytes (channel, value).

If I send it into a [serial] object as a list, the arduino doesn't see it as '2 bytes received'

On the arduino, I"m using "Serial.available()" to report back how many bytes were received, followed by two 'Serial.read' to read the two bytes, and store them as a value

While reading messages that were sent by the Arduino works great (using the [serial] object) I'm struggling with the sending of messages: I'm also not 100% sure if I can just send numbers, or if I need to convert to symbol, or ASCI! Any ideas anyone?

Thanks!!