You can mix it in a blender, otherwise it is a lot of elbow grease.
There is a distinct knack to making it to your taste or memories of Cyprus/Greece.
Always stir the paste in the jar before using as it settles and the heavy paste at the bottom is like peanut butter and the oil is mostly at the top.
Once mixed the paste can be used to make the sauce.
The way I was shown steeped crushed garlic in lemon juice overnight or at least a few hours.
Personally I don't bother.
So crushed garlic to paste according to how garlicky you want it.
Then add olive oil and lemon juice.
Oil makes the paste easier to stir, lemon stiffens it.
I like mine Lemon and garlic strong.
then add the water, I do it in a thin trickle and keep blending until it emulsifies. It might split but you can usually recover it by adding a bit more oil and keep blending.
add water to get the consistency you want some like it thick some like it runny.
Again personally I add a pinch of salt.
Nice to dip pittas chunks in, but very yummy with a nice thick huge pork chop with chips and salad.