One of the easiest and most basic mediums to start with is water colour pencils.
They don't have to be expensive, but do try to get the best quality in your price range.
This soft and gentle medium takes you back to the happy hours you may have spent in your childhood just whiling away the hours, with your pencils and a colouring book.
With some simple rules to follow you can get good results that an be quite stunning and the more you practise the better you will get.
And as you get better, and enjoy the process, you may decide to get better quality materials.
Before you start to colour your images you will need to establish where your light source is coming from, and look at the areas that would be in the shade.
Start with the lighter colours first and colour around the edges of your image. Use light even pressure, and by adding extra colour at the edges it will give definition and shape.
Add deeper colour in the areas that would be in the shade.
The pencils can be used in two different ways.
Either colour directly onto the paper, then take a damp paint brush and blend them in to give a subtle washed effect.
Or add the colour to a pallet and pick it up it from there.
It is not a good idea to take the colour directly from the pencil point as this will wet the wood and eventually it will rot.
This technique can make all the difference to your projects, because a beautiful image, as the focal point, can really add the finishing touch to your card.
It's not difficult to achieve and is very relaxing.