1 - Remove air filter elements going to the air filter to get free space:
2 - Remove Spark plug cables:
3 - Remove Spark plugs with suitable socket. That is 16 mm socket.
Also you'll need torque wrench as to tighten with proper torque. If you have not one. Turn spark plugs 1/2 to 1/4 turn after contact occurs.
The previous change was 30K [km] before. You can see the old and the new spark plugs. The clean one is new of course. It must have 1 - 1.1 mm gap. If not adjust it.
For the driver side plugs, you need to remove window washer water container.
But not fully removal is needed. You may fix it with some elastic holders after turning it a little. You may have enough space to handle replacement of spark plugs.
It is pretty easy. Just half an hour for me.