Swiss rolls are made from a light sponge mixture that contains flour. Roulades are based on a whisked egg mixture and contain very little or no flour, and are moister and softer than Swiss rolls. To prevent a Swiss roll cracking when rolled, trim off its crusty edges then, while it is still warm, put it on greaseproof paper dusted with caster sugar. Roll it up loosely, rolling the paper with it, and leave it to cool in its wrapping. Then gently open up the roll slightly, remove the paper and spread the interior with jam, lemon or lime curd or cream.
Roulades are easier to roll, so can be filled before rolling up. They do usually crack when being rolled, but look attractive when dredged with icing sugar and decorated.