If you don't know your way around a weight room, heading to the gym can be intimidating -- and even dangerous . But paying attention to a few simple rules of proper technique can make you slimmer, stronger and healthier all over.

That's why we asked John Romaniello, trainer, author and founder of Roman Fitness Systems to show us what's what when it comes to strength training.

He'll be helping us tackle some of the most common mistakes we all make while building muscle, plus giving us tips and tricks for better form. This week, we're perfecting the triceps dip .

The Faux Pas: You've probably seen this basic arm move performed on a chair or a bench, but Romaniello warns against this set up. "The position places the scapula in a very unstable position, which can lead to injuries," he says.

The Fix: "Instead, use two chairs [or benches] on either side of the body," he says. This allows you to position your hands even with or slightly in front of your body, he says, which takes some of the pressure off the shoulder blades. Bend at the elbows until your arms are at a 90-degree angle, then slowly press back up.

Tell us how it goes in the comments below, and be sure to check back over the following weeks to fix your lateral lunges, bicycle crunches and more.

Check out more in our Fix Your Form series below:

Photos by Damon Dahlen, AOL

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