Where to Apply
If you want your perfume to project, you should definitely spray it on your skin. This does not mean that perfume does not project from clothes, but it projects much more from skin. However, if you want your perfume to last longer and the smell to stay for a long time, spraying it on your clothes would make more sense.
How to Apply
When it comes to how you should spray it, no matter where you spray your perfume, I recommend spraying it from around 15 cm away. Spraying too close, especially with perfumes that have pressurized atomizers, can make it harder for the fragrance to spread properly and evenly on the skin at full efficiency, while spraying from too far away can cause some of the perfume to be wasted.
More Detailed
If we go into more detail about where to spray your perfume, if you really want to smell noticeable, the places you spray can change depending on what you are going to do during the day and where you will be. In general, what I personally recommend and do is spraying on the skin behind and diagonally below the ears toward the back of the neck — not directly under the ear, but for example, for the left ear, slightly down and toward the back of the neck — and also in the middle of the back of the neck. I personally do not spray perfume on the front of my neck because it is generally not recommended from a health perspective since the thyroid gland is located there, and also because I find that fragrance does not project as well from the front of the neck and the sillage is not as effective. Since you do not normally walk backwards, if you want more of a scent trail, spraying the back of your neck makes more sense. At least, this is what I have experienced. In addition, if you are going to give a presentation during the day or you will be moving around a lot, you can also add a few sprays to the inside of your wrists. When it comes to clothes, honestly, spraying on your skin is usually enough. But if you still want to spray your clothes as well, or if you are only going to spray your clothes, spraying around the chest area, on top of the shoulders, and on the sides of the shoulders should be more than enough.