Maceration
Maceration is the process where the perfume concentrate and alcohol are left together for a period of time so the formula can settle and blend properly before the perfume is bottled. During this time, the materials can come together more smoothly and the overall scent can become more balanced. Maceration has nothing to do with you; perfume houses do this, and in general, the maceration period is longer in niche fragrances.
Resting a Bottle
Resting a bottle is a little different. This is what people usually mean when they say a perfume became better after sitting for a few weeks or months. After you start using a bottle, a small amount of air enters the bottle and the fragrance can slowly change over time. Sometimes the scent may feel smoother, richer or stronger after resting, especially with newer bottles. Every perfume has a different potential. For a perfume to reach its full scent maturity and performance potential takes at least 1 year, and generally 2–3 years, but don't let this scare you because perfumes will usually reach around 90% of their potential after being used for 6 months.
Speeding Up the Process
If you want your perfume to reach its potential more quickly, when you first buy it, use at least 3 ml as soon as possible, then leave it unused for at least 1 month in a dark place that is not warm, and after that you can use it however you like.