Tabatha Coffey brings her signature style and scissors to "The Biggest Loser," tonight. Photo courtesy Bravo.

Celebrity hair stylist Tabatha Coffey is known for bringing shear terror to the salons she makes over on her Bravo reality series, "Tabatha's Salon Takeover."

Tonight, Coffey fans will see her kinder, gentler side (albeit still clad from neck-to-toe in menacing black) when she brings her talents to NBC's "The Biggest Loser," for its popular makeover episode. She reprises the role she took on last season alongside "Project Runway's" Tim Gunn.

Together they help this season's finalists cultivate new looks to complement their slimmer bodies. Gunn will be choosing new clothing, while Coffey will produce new cuts and color for the "Losers" -- and stick around to groom a few of the grizzly guys.

After they have worked their magic, contestants will unveil the new looks to family and friends flown in for the occasion in a classic television "ta-da" moment.

Coffey told StyleList helping "The Biggest Loser" contestants look great was much more fun than making incompetent salon owners cry.

"My favorite thing to do is to create styles that are transformational," she admits. So we can expect the trimmer contestants to have some great hairstyles!

StyleList caught up with Coffey before she began a day at her New Jersey salon, Industrie Hair Gurus, where she still sees clients when she's not busy with her television projects.

StyleList: Experts always say that it's not a good idea to change your look after a major life event; for example a breakup or significant loss. The people you worked with on "The Biggest Loser" are going through really dramatic changes. Was it a good idea to cut their hair?
Tabatha Coffey: Absolutely. You have to approach this kind of thing very carefully. It's a life changing thing to lose all that weight. Then you get out the scissors and say, "Now, I'm going to cut your hair." [Laughs.] It's not always going to go over very well. But I have to say, you are dealing with people, in this case, who are in a lot happier place than if they got divorced or lost their job. I don't think you should cut your hair when you are going through something bad. In this case, they were happy. So it was a little easier to convince them to let me try something new... And a lot more gratifying for me.

SL: I noticed a lot of the female contestants have long, heavy hair and it reminded me of the way some people hide behind baggy clothes to conceal their weight. Were they guilty of hiding behind their hair?
TC: You know one thing I've heard from them was, "I was a fat girl, but I had pretty hair." I did need to explain to them you don't need to hide behind that hair anymore because you are not that girl anymore and you don't have that body anymore. They were going through a very transformational experience and part of it involves looking at yourself in a new way and seeing yourself as the person you have become, not the person you used to be. Their hair needed to transform as well.

SL: Is there a hair style that is an absolute "don't" for a larger woman?
TC: Obviously using your hair to hide and wearing a lot of hair in front of your face can make you look larger, even though a lot of women think the more that's in their face, the thinner they seem. I find the opposite is usually true. Another thing that is significant is where you hair hits along the jawline. It can either thin out your face or make it appear larger. That can be a very individual thing, which is why consulting with the client is so important. I think bangs and layering around the face can make a huge difference, by slimming and showing more structure.

SL
: Was there a makeover that just stunned you?
TC: I have to tell you -- all of them [did]. It was so inspirational to work with these clients. I walked away feeling so proud of them and feeling like they all looked spectacular. There is nothing more exciting as a stylist then to do work that transforms.

SL: You mentioned consults, which is something you always stress when you are rehabilitating salons on "Tabatha's Salon Takeover." What should a client expect during a consult with his/her stylist?
TC: It's a matter of making sure the stylist really understands you. They need to know what your dream look is, how much you are willing to pay for it (in terms of maintenance and upkeep) and how often you are willing to come in. They need to know if you are a busy mom with four kids who literally has five minutes in the morning. They need to know if you are someone willing to spend hours on your hair. They need to know what hasn't worked for you in the past and why. I ask all these questions and more. If your stylist isn't asking you questions, you need to begin the dialogue. But they should ask.

SL:
This season you've visited some salons that were so filthy I began to worry about what's lurking beyond the cutting chair at my own salon. How do you know a salon is clean?
TC: We've had some really interesting salons and situations this season. Disgusting in a few cases. My advice is use your eyes. It should be obvious. If you see brushes with hair still in them, floors that are not swept, towels piled on the floor, disgusting rest rooms, you need to go somewhere else.

Catch Tabatha when "The Biggest Loser" airs tonight at 8:30 pm on NBC, then again on "Tabatha's Salon Takeover'" at 10:00 pm on Bravo.