Lift the front up as high as it will go, without sliding over the front of your breasts.  This will make sure the back stays low, for proper support. This will also ensure you get lift in front, where you want it. Start from just behind your armpits, and push as much as you can into the cup.  Breast tissue is soft, and if your bra fits properly, it should stay where you put it. Grasp the front of the bra and jiggle slightly to settle everything into place. With a properly fitted bra, the apex of your breasts should be approximately halfway between your elbow and your shoulder. Doing so can make the bra uncomfortable, and this can affect your mood and posture.   Never tighten the straps so much that they put pressure on your shoulders. This will cause you to slouch forward. Never tighten the straps so they pull the bra up at the back. Keeping the back band straight across is important for adequate support in front. When buying a bra, hook into the loops at the very end of the band. This gives you a way to tighten the bra as it stretches out over time. Your breast size will change along with other changes in your body.  Get fitted every time you lose or gain more than 10 pounds (4.5 kg) or have hormonal changes such as with pregnancy or hormone therapy.   Many lingerie stores and departments offer free professional fitting. Don’t be embarrassed! These women are usually very kind and professional, and have seen it all before.  Try to get fitted at a store with a wide range of brands and sizes, otherwise the information you get might be limited to what the store actually sells.

Summary:
Hook the bra at your waist, then pull up only in the front. Lean forward and smooth all the soft tissue forward. Know how high on your chest your breasts should end up. Don’t overtighten the closures or straps. Get a professional fitting regularly.