First, log in to your SurveyCTO account and navigate to the "Collect Data" section. Here, you should be able to view all your collected forms. Choose the form whose data you want to export. Ensure you have the necessary permissions to access and export the data.

SurveyCTO allows you to export form data in various formats. For this step, export your data as a CSV file. Click on the "Export" option for the chosen form and select "CSV" as your preferred export format. Download the resulting CSV file to your local machine.

If you haven't already installed Python, you'll need it to convert the CSV file to JSON. Download and install the latest version of Python from the official Python website. During installation, ensure you check the option to add Python to your system PATH.

Open a text editor or an Integrated Development Environment (IDE) and write a Python script to convert the CSV file to JSON. Use the following basic template, modifying it according to your CSV structure:

```python
import csv
import json

csv_file_path = 'path/to/your/file.csv'
json_file_path = 'path/to/your/file.json'

# Read CSV and add data to a dictionary
data = []
with open(csv_file_path, mode='r', encoding='utf-8') as csv_file:
csv_reader = csv.DictReader(csv_file)
for row in csv_reader:
data.append(row)

# Write data to a JSON file
with open(json_file_path, mode='w', encoding='utf-8') as json_file:
json.dump(data, json_file, indent=4)
```

Save your script with a `.py` extension, for example, `convert_csv_to_json.py`. Open your command line or terminal, navigate to the directory where your script is saved, and execute the script by typing `python convert_csv_to_json.py`. This will generate a JSON file in the specified path.

After running the script, navigate to the location where the JSON file was saved. Open the JSON file using a text editor or a JSON viewer to verify that the data was converted correctly. Ensure the structure matches your requirements, and all records are accurately represented.

If you frequently need to convert SurveyCTO data to JSON, consider automating the process. You can schedule the Python script to run at regular intervals using a task scheduler like Cron (Linux/Mac) or Task Scheduler (Windows). This step will save time and effort, especially when dealing with large datasets.

By following these steps, you can efficiently move data from SurveyCTO to a local JSON file without relying on third-party tools.