New To Midi, Can't get Keyboard and Reason 1 talking Options

Greetings serious music pros,

We have a Yamaha PSR 280 keyboard which we are trying to midi up to our G3. We are using Reason 1 and I am using OMS for midi connections. The trouble is we don't know what we are doing and things are not working.
Q.1 What do we have to do in Reason to talk to the keyboard.
Q2 The same question re OMS, how do we use it to set up midi.
Q3 And finally, the keyboard, a Yamaha PSR 280, cables - we have 2 midi connected to in and out on the keyboard and in and out on the Roland midi box. We have 1 serial cable connecting the midi box to the G3 via the printer port.

I guess what we need is a good tutorial. I have found a couple but they tend to assume some basic knowledge or prior music skills. We (my son and I) are both on a steep learning curve with music. He composes using Reason and I make online musical interfaces/instruments with Flash.

Platform; Mac beige G3 233, 224 RAM, 60 Gb HD, CD+Floppy, Lacie/Yamaha 4x4x16 burner, Microtek E6 scanner, Zip 100, ext modem.


Cheers, Barrie and Carl
ad hoc graphics