Grow Plants From Cuttings 

Choose and mix the preferred medium for the plant you have chosen. 

If possible, have the planting medium prepared in the pot when you take the cutting. If this isn't possible, temporarily wrap the cuttings in wet paper towels, then cover in newspaper or a plastic bag.

Use a sharp knife to take the cutting, and don't make the cutting too large. Four leaf nodes (leaf joints) are usually sufficient. 

Cut the leaves from the portion of the cutting that will be immersed in the medium.

Apply a rooting hormone (or a willow water soaking) around the bottom of the cutting.

Use a pencil to poke a hole in the planting medium. If several cuttings will fit in the pot, poke several holes.

Carefully slip the cutting(s) in the hole(s) so that the bottom 2 leaf nodes are below the soil line.

Gently firm the medium to remove any air pockets.

Water with a very gentle spray making sure that the entire pot is well soaked.
 
Cover with plastic and place in indirect light until rooted.

Watch closely for new growth for the next 2 or 3 weeks.

When tiny new leaves have formed, remove the plant from the medium by gently tugging a larger leaf.

Place each rooted cutting in it's own pot of planting medium.

Water well.

When all danger of frost has passed and the ground has warmed, transplant to the garden.

Tips:
Don't take cuttings from diseased or wilted plants. 
Remove any flowers or flower buds from the cutting.
Place in indirect light until rooted. 
Slowly acclimate them to brighter light, increasing exposure few days until they're ready to transplant to the garden.