Create your account here if you dont already have https://www.dropbox.com
After signing up open https://www.dropbox.com/developers/apps
Click Create app
Fill next form like below and click Create app button.
Click Generate button under Generated access token
Copy that generated access token.
And paste in Free Snipping Tool > Options > Dropbox > Access Token. field.
It will be saved automatically and we are now ready to test our Free Snipping Tool integration with Dropbox