Well, if its a guy, and he is shanking a woman while another guy is shanking him...
There are no signs. If you are bisexual, no one will know for certain unless you tell them.
There is only one way to tell: you have ask her.
There is only one way to make your parents believe that you are bisexual. You will just have to tell your parents.
'I'm bisexual'
I would tell your bisexual friend that even though its hard to tell them but you have to because you're his friend. then nicely tell them that the other guy isn't interested and that there are better people out there for him.
They will tell you if they trust you. If you think you are a good and accepting friend, then they may tell you. They need to know that you will be supportive and not judgmental. They need to know if you are a gossip or if you can keep a secret.
Two ways. You can go up to random people and say 'Hi, I'm a bisexual' Or you can do it subtly. You can find a friend you trust and tell them, or you can let a little conversation be overheard (or a text message read) by a gossiper (the best people for the job). There are also many more ways of doing this.
In general, no. Some people find it easier to be bisexual, and some gay people often identify as bisexual to test the waters, so to speak. However, this has resulted in a phenomenon called bisexual erasure. People are more likely to believe that, no matter what a bisexual person says, they must prefer one gender or the other, which can cause great frustration for the bisexual community.
he is secretly bisexual, don't tell...
If you fall in love with and is sexually attracted to both genders you are bisexual.
they find out that they're bisexual and if they think you are good friend and not a gossip or jedgemental then they will tell you i know because i'm bisexual and if anyone is gonna ask how i know this is my answer i had a crush on a male friend in yr 5 and i have a girlfriend now
You can tell by the gender of the person/people you are attracted too. And if that's still confusing, you might be bisexual.