If you don't have a Business Intelligence Center site collection located on your farm, you will first need to create one via the following steps:
- Open Central Administration on your SharePoint 2013 environment
- Select Application Management
- Under Site Collections, select Create site collections
- Choose the appropriate web application where it should be installed
- Enter an appropriate Title and URL for your new site collection
- For Select experience version, select "2013"
- For Select a template, click on the Enterprise tab and select Business Intelligence Center
- Select an appropriate Primary and Secondary Site Collection Administrator
- Click OK
Once your Business Intelligence Center site collection is in place, use the following steps to obtain the PerformancePoint Dashboard Designer:
- Log on to the Business Intelligence Center site collection via your browser
- In the left navigation panel, select PerformancePoint Content
- Click on the tab that reads "PERFORMANCEPOINT"
- Click on the Dashboard Designer icon
- Click the Run button when prompted
Once the installation is complete, the Dashboard Designer will open and you can now begin working on all those other tutorials you found.