I've tried different kinds of meringue recipes, but none gave me a stiff and glowy meringue. Any suggestions?!
The most common reason for egg whites not whisking into a firm, glossy meringue is that there is some fat in the white. Fat will prevent air bubbles from forming when the egg white is whisked. When separating eggs be sure that absolutely no yolk gets into the white as the yolks contain fat. Also check that the bowl and whisk are both grease-free. Try to avoid plastic bowls as grease tends to cling to them (even after a good wash) - glass, stainless steel or copper bowls are preferable. Wiping the bowl and whisk with some lemon juice will remove any residual traces of grease and the acidity of the juice also helps the whites to produce a better volume on whisking.
When making a meringue the egg whites need to be whisked to full volume before the sugar is added. Whisk the whites to stiff peaks, if you lift the whisk then the whites should stand in a pointed peak. Check frequently when whisking as the whites can become over whisked easily and start to liquify again (over whisked whites look a little like cotton wool). Once your egg whites have reached stiff peak stage whisk in a little of the sugar from your recipe to help stabilise the whites (about 1 tablespoon per egg white) and whisk the whites back to stiff peaks, then fold or whisk in the remaining sugar, following your chosen recipe. Use caster (superfine) sugar as this dissolves more quickly for a smooth and glossy meringue and try to use the meringue as soon as possible as it will soften as it stands.