Mixing cement can be accomplished a few different ways. For small quantities cement can be mixed on a flat surface such as an old piece of plywood, for larger quantities it is much easier if you hire or buy a cement mixer. You can often hire an electric or petrol driven cement mixer from your local tool hire company.
When cement has been mixed with sand and water it is often called mortar. It is essential when mixing the mortar that it is mixed properly when dry, then when the sand and cement is properly mixed water can be added in small quantities until the correct consistency is achieved. For some applications you can add other ingredients to the mix, for example hydrated lime can be mixed with the mortar which is common when re-pointing, the addition of the lime to the mix can make the mortar more flexible and less prone to cracking.
Plasticiser can also be added to the mix to make the mortar more easy to work with, some people use washing up liquid for this purpose, but it is not recommended as there are dedicated products made for this purpose. Integral waterproofer can also be added to the mix as this can be useful for rendering as, once it is dry the render will be waterproof. When ever an additive is added to the mix it is essential to follow the manufacturers instructions, normally most additives are added to the gauging water.
Mixing cement by hand on paving stones
When measuring the ingredients for the cement it is advisable to use a dry container such as a small bucket as using a trowel or spade will not guarantee an even mix as the shovel can be heaped, which can give an inconsistent mix.
This plastic cement mixing board is ideal for hand mixing cement.
Here we are mixing mortar at a ratio of 4 sand to 1 cement by volume.
Start by putting the correct amount of sand onto the mixing board
Then add the cement
Mix the sand and cement together until you get a consistent colour
Slowly add the water and mix the mortar together.
Note how this water is frothy, this is because plasticiser has been added to the gauging water
Mix the mortar and add water as necessary until the desired consistency is achieved
For information on mortar mixes please see here-