According to "A guide to neighborhood placemaking in Chicago," there are three phases involved in a placemaking process: Assessment, Planning, and Implementation. This guide further detailed the process cycle into 11 steps.

Assessment: understand and evaluate the neighborhood.

Observe Space Challenges: It could be started by an individual or a group. First, discover the surroundings and then use maps, photos, or videos to capture your own "insight" of the neighborhood.
Select a "Site": once initiators collect all the information, they can check with the local authority (such as mayors, planning departments, or neighborhood associations) to see if there is any restriction on their chosen location.
Identify Stakeholders: once initiators discover the challenges and understand constraints, expanding influence and inviting a partnership is essential. These partners could be people who live, work, and play in the area, a non-government organization, a local community group, a judicial office, professionals, and individual experts.
Collect Data: this step is similar to "understanding the why." Initiators begin to collect data and evidence to understand "why" some challenges happen (at a particular location or time.) Techniques could include interviewing, behavior mapping, counting, or tracking. (1)

Planning: translate the group's ideas into an actionable plan

Assemble the findings: conducting a workshop to gather groups' discoveries, comments, and collected information into an organized format.
Translate findings into specific recommendations: developing solutions after reviewing those challenges and ideas.
Express recommendations to visible form: this step is also called "visual concept plan" or "visioning." The initiators work with professionals to develop a plan and simulate the outcome in models or illustrations.
Generate summary presentation: arrange the group's findings, recommendations, and supported illustrations into an understandable presentation. Thus the group can always revisit the summarized plan during the implementation phase and see if their action follows the initial vision.

Implementation: put ideas and visions into action

Short-term action: some ideas can easily turn into actions. For example, basic activities such as clean-up or temporary events can be done without much funding.
Long-term design and management plan: including technical expertise, architect, engineers, and other professionals who can help transform the vision into reality. On the other hand, asking for the local government's involvement in essential services will help maintain the area and ensure the group's efforts are constant.
Review and repeat: after a period, the group can review the progress and see if the project plan is valuable to the locals and worth repeating and implementing in other locations.

As mentioned in the article, placemaking is a "never-ending game." improving our or neighbor's environment is something we call can learn, benefit from and pass it down to generations.

Notes and references:

During the collect data phase, initiators can also look up the invaluable data published by the Census Bureau and have a comprehensive perception of their area.
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Interested in how others make their place? check out Case Study: Noashima Island vs Pike & Rose