How do I round this binary number to the nearest even

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I have this binary representation of 0.1:

0.00011001100110011001100110011001100110011001100110011001100110

I need to round it to the nearest even to be able to store it in the double precision floating point. I can't seem to understand how to do that. Most tutorials talk about guard, round and sticky bits - where are they in this representation?

Also I've found the following explanation:

Let’s see what 0.1 looks like in double-precision. First, let’s write it in binary, truncated to 57 significant bits:

0.000110011001100110011001100110011001100110011001100110011001…

Bits 54 and beyond total to greater than half the value of bit position 53, so this rounds up to

0.0001100110011001100110011001100110011001100110011001101

This one doesn't talk about GRS bits, why? Aren't they always required?