Using but in a sentence

But is a conjunction. It joins two sentences
To begin a sentence with but is grammatically wrong.
Here are some nice proverbs that use BUT

• Do not look where you fell BUT where you slipped
• Don't make love at the garden gate, love is blind BUT neighbours aren't!
• Everybody wants heaven BUT nobody wants to die.
• It's nice to be important BUT it's more important to be nice.
• It's only rock 'n' roll BUT I like it

But that does not mean I cannot begin with a BUT! Many writers have cheerfully ignored such rules!

Going strictly by rules of grammar it is not correct to say
But I do not have the patience ...
But I am scared of technology ...
But it is boring to sit and prepare a speech ...
But I am always harsh and curt ...

On the other hand, the right thing is to say is this.
I do not have the patience, but ...
I am scared of technology, but ...
It is boring to sit and prepare a speech, but ...
I am always harsh and curt, but ...
Hey, come to think of it, the conjunction BUT joins two sentences
and minds
and hearts
wow!
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Miracle in my kitchen
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