Ah, so it's a homework problem. What have you found already? What part specifically are you stuck on? There are basically three things you need to consider.
The first is getting the right inductance. There should be lots of sources out there to help you decide how many turns around what kind of core material you need. Long ago I saw a pretty good intro to this in the ARRL Handbook, but I don't know if current issues still have that. Surely there must be stuff on the net about this. Another place to look would be web sites of core manufacturers. They may even tell you outright how many turns is what inductance.
The second issue is to make sure your inductor doesn't saturate below 1A. The core manufacturer should also be able to tell you how many ampere-turns it takes to saturate each core. Or, they may tell you the energy a core can store. Use E = (I**2 L)/2 to find the energy you need and then make sure the core can handle it.
The last issues is your 220V spec. That's up to the insulation on the wire. "Magnet wire" is usually used for such things because the insulation is thin and therefore doesn't take much space in the windings. That also means it may not be good to a high voltage. However, if you're careful you don't need the insulation to withstand the full voltage. For a single winding layer, the full voltage will be applied accross the ends of the windings, but adjacent turns see only a fraction of that. You do have to be careful about routing the wires that come off the ends of windings. For multiple layers, the same principle applies, but not so much since there are generally fewer layers. You can insulate between layers with electrical tape to get around that, but be careful of creepage distance.
