In learning how to dive, some scuba instructors may point out a few things beyond the skills you learn. Many will not. Neutral buoyancy is an art and craft that must be worked on all the time. A friend and scuba instructor, Mike Shea, talks how buoyancy is a perishable skill that must be practiced. I couldn't agree anymore with that statement. There are three things you can do, right now, to work on the craft of neutral buoyancy.
The first thing you want to do is shed the weight. You want to do a buoyancy check before and after a dive to fine tune the amount of weight that you actually need. It's even more important to do it on empty today so can determine that you do have enough weight to keep you floating eye-level on an empty BCD. You should start to sink once you exhale air out of your lungs. By being over-weighted for a dive, it will cause you to exert more energy and have a harder time achieving neutral buoyancy. Along with the extra exertion you will consume or use more air in your tank. This will limit the amount of time you can actually dive. The opposite of this is not having enough weight. This can make your dive miserable. Constantly having to pull yourself down or hold on to something to at least enjoy the dive a little more. With this, you to exert more energy and consume more air. As you can see having the right amount of weight could help you achieve neutral buoyancy.
The next thing to do is control your breathing patterns. Your breathing pattern should be long but comfortable. I typically tell my students to count for five seconds while inhaling and five seconds while exhaling. This technique will help you achieve neutral buoyancy; it will also keep your breathing calm while diving. By having this long breathing pattern, it prevents you from holding a little bit more air in your lungs causing you to drift up (being positively buoyant) and adding more weight than you actually need. This can be misleading to a new diver. The habit of accidentally holding a little bit more air in your lungs instead of exhaling fully, you are forced to add more weight to stay down.
The third thing you could do to help achieve neutral buoyancy is practice. Nothing will increase your ability to achieve neutral buoyancy other than practice. Just like a baseball player and or one who golfs, they can become better by increasing the number of times they actually try. The same is true with scuba diving. The number of times you practice a certain skill, such as buoyancy, will only make you better. Practice will allow you to naturally achieve neutral buoyancy just by the continuing to practice the skill.
Neutral buoyancy is a perishable skill. The skill must be practiced over and over again. Anytime you enter into a new environment, add new or more equipment, you will have to go through these this three-step process all over again. In the end, it will be worth it due to the fact that you will enjoy your drives much more and extend the amount of time that you can actually stay on one dive. Every scuba divers dream is to make that one scuba moment last just a little bit longer.