Safety First!
To guarantee proper grouning and avoid putting the machine on a static charge level against the ground of the house you need to properly connect the ground wires to the ground wire of the house. This is done by using a grounded power cord with a C13-plug on the machine end and a proper, grounded plug fitting your sockets on the other end.
Proper plugs
In most of the continental EU (safe France), you usually can use a Shuko (Schutzkontakt) TypeF/CEE 7/3 while the Type E+F/CEE 7/7 plug adds France on the house end, as these are proper grounded 3-wire plugs. But in the UK you need a Type G/BS 1363 plug, with or without a fuse.
Fuses
Because the machine operates on mains voltage in the PSU, it usually already has a fuse mounted inside the PSU, so a fused plug is not strictly needed, however it is not a bad idea to include an extra fuse - technically you'd end with 3 in total if you are properly grounded because the circuits breaker-box fuse is there too.
Wire Extensions
What would be a bad idea though is to use any extension cord in the wiring that is not grounded because it might use a plastic ground pin or lack the metal contact surface needed to ground the cord.
Improper plugs
A 2-wire "Europlug". Europlug CEE 7/16 is only rated for 250V/2.5A and not grounded, thus it is not suitable for operating a 3D printer , and I strongly advise not to use a gritish folding plug either as it is not grounded!
Safety Mantra!
Let me reiterate this: Only use grounded connections from machine to socket or you risk creating a charge on the machine!
Check your socket's ground if you are not sure it is properly installed. For further information, I strongly suggest watch Angus (Makers Muse) with how he discovered a problem with his extension cords leading to a potential dangerous charge on his machine and DIY3D Tech explaining the basics of the problem and how to solve it to you again!