Create yourself a table. Use a piece of A3 paper. On the left put all the electoral systems you need. In the next column, add the basic overview of what happens. Next, where it is used. Then advantages and disadvantages. Finally, add a few facts and figures for the elections it is used at. (E.g. FPTP used for Westminster elections, small parties are disadvantaged – UKIP 2015 with 12% vote and 1 seat).