When everyone is tucked in then pour your brine over and give the jar a few good taps to knock out any air bubbles, make sure that all your cucumbers are under the brine. If they are not covered then you might need to rearrange and poke them down a little bit.
You can chose to put either a lid or an airlock on at this point, if using a lid you will need to remember to “burp” regularly to prevent the gas from building up which can actually cause a lot of mess and sometimes a mini explosion.
Now they are ready to be tucked away, they will prefer somewhere dark and without extremes of temperature. Ideally this is also a place that isn’t too out of the way so that you can remember to check on the cucumbers, if it is then I would set a reminder on your phone so you don’t find a horrible mess later down the line.
If you have a normal jar with a normal lid that will need burping then you might need to “burp” as often as twice a day for the first week when things are really active, the bacteria are going to be hard at work and farting away.
During your burps it is worth checking if any cucumbers have floated up to the surface and if they can be resecured down again or if they need to be weighed down. You can purchase very expensive fermentation weights but I haven’t tried them yet, I am too much of a cheapskate. It is quite common to use another vegetable or (I have also used a slice of lemon) to wedge everything down under the brine level again.
These cucumbers should be ready to eat in 2 weeks but are better after about a month, this will of course be different depending on your personal preference as well as a host of other factors (cucumbers, salt, water, temperature etc).