How to create a butterfly garden?

I don't specifically mention about the butterfly species, nectar plants and host plants since they can be varied depending on the geographical area. 

1. Research about butterflies

You may refer butterfly field guides to find the common butterflies in your area. In addition, use public forums dedicated for discussions on butterflies in internet. Most important thing is your own observations. Spend some time to closely observe the butterflies in your area and try to identify them. Record the observations.

2. Select nectar plants

Some plants are favored by most of the butterfly species. Blue snakeweed is one of them. In addition, some butterflies have special attraction to certain plants. Research and observe to identify such plants. Some of the plants can act as weeds. So, carefully choose the nectar plants depending on the size of your garden. 

3. Select host plants

You should find the local host plants depending on your region. Most of the host plants are considered as weeds. Therefore, you may need to find a way to control them.

4. Plan & plant your butterfly garden

You should consider about the fully grown size of the plants. For a small garden, choose appropriate host plants. Two such examples are;
                                    Air plant (Bryophyllum pinnatum) : Red Pierrot
                                    Fringed spider flower (Cleome rutidosperma) : Psyche