Use exactly the same system as you would for an engine fire on take-off...
Do your recall items
Ask for max cont thrust on the other engine (since you still have to climb above MSA), and level change on MCP. If you're flying 250, I would come back to 210 to change speed for altitude. You can leave LNAV engaged since you will probably make the SID climb gradients even on 1 engine. If you find yourself heading for the Alps however, you should consider turning away from them. e.g Departure out of Nice, headin North, advise ATC and turn south towards the sea...
Advise ATC of your problem (Pan if fire extinguishes / Mayday if the fire stays)
Do the rest of your non normal checklist
Take a decision about where to divert. With the engine still on fire I would recommend a 'rushed' approach into the nearest suitable airfielf, even if the conditions are CAT 2/3... You don't want to stay in the air with that..
If the fire has extinguished, you find yourself in a PAN situation where, 'just' a 'normal' single engine INOP...
Hope it never happens to you outside the simulator..
