The World Carefree network run a "Street Conversion Design Contest" which is similar to PARK(ing) ideas but it's more conceptual drawings than a physical intervention.
Designers tend to work in several design phases. Simplified the thinking process tends to go -
1) Concept and Options Development
2) Detailed Design
You will intuitively work though these design phases in your own PARKs
1) What am I going to PARK?
2) How the heck do I build that?
3) Lets go build it!
You can also start to understand how our cities get built in these phases
1) What do we want our city to be? (Visions, Objectives, Principles, Policy etc)
2) What are the projects that will make that happen? (proposals for buildings, infrastructure, programs etc)
3) Let's go deliver something
Of course in reality its a little bit more complex, but generally it's the integrity in which we move through phases 1 to 3 which ultimately determines how successful our end results are. (...whether it's about a city, a building, a personal action or a PARK(ing) space)