To contribute to ThinkUp, you will want to manually install the files direct from the source repository.
Here are installation guides by operating system.
ThinkUp is under rapid development right now, so files change fast. If you used
git clone git://github.com/ginatrapani/ThinkUp.git
to get ThinkUp files initially, use
git pull origin master
to get updates.
If there's been a database migration since the last time you built your database (check the
db_migrations folder), run the SQL script against your database to update it.