The switch will need to be double pole and the plug fused to 3 Amps.
Flex to plug brown=live, Blue=neutral, CPC/earth, although not required I would still introduce one between the plug and switch, then switch and fan, and leave in terminal block at fan.
At double pole switch flex from plug:
Live brown to supply/in live
Neutral blue to supply in neutral
Flex between switch and fan:
Switch:Live brown to load/out-Fan: live
Switch:Neutral blue to load/out-Fan: neutral