Asking the guys...
Learn the material better than them. Become the expert.
I teach automotive classes and only have two feamales this year..buttruth be told they seem to do better around a bunch of guys than the guys do around them. I would just be myself and don't take any crap from them. :)
Best advice i can give is too put yourself in the position you feel good in.
First step would be to know what you want to tell them. This comes togheter with the 2nd part. Know what you are talking about. If you do this in a good way this gives you a plan to fall back on. If possible you can make a powerpoint with headlines. So you can look at what you want to say. This also makes it easier for others to follow you.
Set the rules early. If you dont feel comftable with situations make sure the rules are the first thing you make clear. Its impossible to set these later. It will be too late then.
Put on clothes that you feel secure in. Specially for a first time this can really help.
Take your time! Dont rush it. When you make a mistake or lose track. Dont panic keep your calm and you will see your audience will stay with you.
Not sure if it helps to remember that as a woman you have like infinite power over men and this sometimes frightens them.
Just be nice and chill out and know that inside you is the power of a thousand suns
Well Ms.Aarti... Do not try to fit in by changing your persona... Be the same unassuming person you are and am pretty sure not just the guys but everyone will treat you with the respect you so truly deserve
My two cents,...
When speaking to a male, do not lose eye contact while communicating. Even if they do.
Depending on the culture, do not limply shake hands. This is an unconscious indicator of character.
Do not lower your chin. Yes, I know, dogs judge intent that way too. That 'guys are dogs' thing stopped being funny three presidents ago.
Look up 'mercurial'. Don't be that way.
Lower the tember of your voice. Alto... go Soprano. Soprano... maybe Tenor. Baritone is right out. Your a woman not a Bass!
Last, I agree with the most often said thing so far...
Most guys respond negatively to BS. If you don't know, stop talking. If you're wrong, admit it.
Remember, you're a woman. If you're half as well cultured as my wife, you can think and talk faster than the guys. The reason, probably, for the shyness is you are outside your comfort zone. Enjoy it.
What's the worst thing, you learn something?
Good luck. Don't be afraid.