First of all, I don't understand the generations system that others use, my rule is simple: these ''gens'' is one bunny done in different ways. It's up to you what way to do the bunny works best, I will show you all the bunny hop styles that I know of.
I might make a video showing of me doing most of them but for now, here are the basics.
Keys: Hold Ctrl, Tap Space + S
Notes: This method is good for beginners, but pretty much useless.
It is mainly used to get you used to the timing and pace that you need, so you can use the
timing on other bunny hop styles.
Keys: Start with Method 1, Then Tap S Then Space, Repeat
Notes: I use this style now, You can go incredibly fast if you have your timing set right.
To go faster and increase your speed, Just linger the S key, instead of tapping it, hold
it for a good sec, then jump then hold for a sec. repeat
Keys: Hold CTRL + S, Tap Space As You Go Along
Notes: One of the EASIEST way to bunny, most of the time you are visible though.
The best thing about this bunny, if done correctly. You can go faster then the ''4th gen'' and
no its not a joke o.o
Keys: Run, Jump, Crouch, Let go of W, Jump, Jump, Jump.
Notes: Rather harder then the other methods. This bunny, also called
''4th gen'' is a bunny
referring to going forward rather then backwards.
This bunny is very fast and about the same speed of a normal running ghost
which gives this bunny an advantage
over the breath listeners.
Those are the ones that you should use for now, There are a bunch more. but useless and these are common and somewhat easier.
Places to practice these bunny styles would be in lab/haken and even metro. I am not sure if lost relics is a map where bunny hop can be done correctly and usefully.
Some people choose to bunny from a hidden prospective, reach their target and then kill, Rushers decide to do the risky and start their bunny right in-front of their targets.
If you time your bunny hop perfectly, and tap space at the perfect time, your jump will manipulate the speed of your last jump's speed, that is what 4th gen/method 4 is. You can also mix method 4 with method 3 for a different pitch into the bunny hopping era.