First of all, know what you're purchasing. Perfume has the highest oil content for fragrances. It lasts the longest, and costs the most. Eau de Toilette is a mix of oil and alcohol. Lasts a good while, but not as long as perfume. It's usually about 1/2 the price of perfume. Cologne has the highest alcohol content, is the least expensive, and lasts a relatively short while. So, pay more but use less....or pay less and use more. Your choice.
The fragrance I like is CK1 for women (also makes one for men). It's a clean, citrus and spice scent. It's not overpowering (unless you use 1/2 a bottle at a time).
A good way to put perfume on: dab behind ears, onto wrists, in the crook of the elbow, and on your tummy. Anywhere there is warmth. It's also nice to rub a small amount into your hands and through your hair.
If you're using a spray or spritzer type application: spray into the air and walk into the mist. Don't spray directly onto skin, as this causes a high concentration of scent on one location.
A good rule of thumb for either women's or men's fragrances: if someone can smell you from farther than 1 foot away, you've got too much on. The office is not the place for perfumes; you want to reserve scents for those who get close to you. There is *nothing* I find more annoying and obnoxious than an overpowering scent in public places. (Especially if it's one I don't care for.) Too many competing fragrances equal one massive bad scent.