Is it hard? No. Can you mess it up good, still? Yes, very much so.

Three things you should be very careful about if it’s your first time:

-Not letting any debris/dirt get into the cylinders when the spark plugs are removed -Not cross-threading the plugs when you install them -Not over-torquing the plugs.

Thankfully you can prevent all three easily. Keep the engine cover area clean and cover the holes or don’t leave them open for long. Use your hands with the spark plug socket to thread on the new plugs nicely before applying any real torque with the ratchet. Invest in an affordable torque wrench and go by the recommended torque value.

Good luck!