How to make electrostatic shield of Toroidal transformer

When customizing the toroidal transformer, isolation transformer, waterproof transformer.
there are customer requirements that the transformer shouldhave electrostatic shielding function, so why should 
the toroidal transformer add electrostatic shielding, what material is it made of? What should we pay attention to 
when making it?
The shielding layer of the toroidal transformer 
electrostatic shielding is located between the primary and secondary, and the electrostatic shielding can effectively shield the high-frequency interference between the primary and secondary. In the power transformer, electrostatic 
shielding can effectively shield the high-frequency 
interference from the power grid, and also can effectively shield the transformer from the high-frequency interferencegenerated by the application circuit to the power grid.

The following points should be noted in the production of electrostatic shielding of toroidal transformer: 
1. The shielding layer can be made of 0.3-0.5mm copper foil or aluminum foil, but the copper foil must be reliably connected with the lead wire, otherwise the copper foil potential will be suspended. 
2, Must not form short circuit turns, but try not to leave a gap. Otherwise, the transformer burns down, not only the problem of heating, but also not in time to heat, the 
transformer burns down immediately. 
3, The lead line must be reliably grounded or connected 
with the lower voltage of the coil head, otherwise it will be suspended. 
4. No burrs after production. 
5, Tightly wrapped in the hard insulation cylinder, so that it has better mechanical strength. 
6. The lead wire must be wrapped well.