2. Sift the ingredients well
Even if you see no lumps, proceed to sift the dry ingredients well. You may be tempted to sift more than once, but if you do it slowly and carefully, one time is enough.
Macaron recipes call for exact ingredient measurements, so if you do batches of macaroons and want to save time, you can prepare and sift the dry ingredients in one sitting and store them in portions for future use. Buying ingredients in bulk will also save you money. Imagine feeling not at your best one day, and craving for some macaroons, but the prospect of having to prepare even the tiniest ingredients from scratch makes you just want to jump to bed.
To prevent this, and also to ensure that you will have macaroons that have consistent quality, prepare what you can prepare in advance in bulk, and save for later. Usually, people do this with icing sugar and almond flour.