A solution would be similar to lemonade powder dissolved in water. The lemonade powder acts as the solute and water acts the solvent. When stirred, the mixture appears yellow throughout and this would be classified as a homogeneous mixture.
A colloid is formed when particles are sized between 1 and 1000 nm. It is a mixture between a homogeneous and heterogeneous mixture. The particles will stay suspended permanently in the solution. An example of a colloid would be Jello or any gelatinous mixture.
A suspension is for particles larger than 1000 nm. The particles are too large to stay suspended in the solution and will fall out over time. The most common examples of this would be sand in water or dust in air.