Make sure the mixing bowl is thoroughly clean and grease free before beating the egg whites up. Grease inhibits the egg whites from whipping up, so you will not be able to get it mixed up to bake into a pavlova.
Separate the eggs carefully, as any egg yolks will have a similar effect as grease, and prevent the egg whites from whipping up.
When adding sugar to the egg white mixture, add it a spoonful at a time. This allows the sugar to be properly incorporated with the egg whites and dissolve into the mixture. This is important to give a smooth and not grainy pavlova.
A great (and rather bold!) way to test if the egg whites ready is to turn the bowl upside down (over your head if you are REALLY brave!). If they are beaten to stiff peaks, the pavlova mixture will remain in the bowl and not fall out. If they are not, they will slide out. Do it slowly so you can check, and also so you can avoid the mess and clean up in case they are not ready yet!
After baking the mini pavlova nests, it is really important you do NOT to open the oven door. Opening the door will change the temperature of the oven really quickly, resulting in cracks in the nests. This is why it is vital to leave them to cool completely in the oven once baked. Leaving them to cool in the oven overnight is ideal so they can cool slowly.
Make the whipped cream filling a few hours before you need it and pop it into the refrigerator until required. This makes it much more convenient to bring the whole lemon blueberry meringue together quickly.
Remember you must serve the blueberry meringues as soon as you have assembled them.