Bug management/Triage tasks

There are a number of ways to start triaging:

Triage a single application
Pick up the product or component that interest you, or which you know about, or are willing to learn, or happen to use. You can query for existing open reports and take a look at issues that interest you, for example in order to update them by updating the Version field, or noting that they have been already fixed in the version you use (please mention the exact version that you use in a comment, also see the section on reproducing in the Triage Guide).

Triage the Extensions category
Wikimedia Bugzilla hosts many extensions that are developed by volunteers. Their maintainers are always happy about a helping hand. The steps explained in "Triage a single application" also apply here. You can explicitly search for bug reports on applications in Extensions by setting the product to "MediaWiki extensions" on Bugzilla's query page.

Triage the latest incoming reports
Take a look at the latest incoming reports of the last two weeks and try to reproduce them, or ask for missing information, or add additional information. See the Triage Guide.

Try to reproduce reports that are UNCONFIRMED
Many reported problems cannot be easily reproduced. Take a look at bug reports in UNCONFIRMED state, try to reproduce them, and feel free to add a comment either with instructions to reproduce or that you could not reproduce it and mention the version that you use. Please do not add such comments for reports in NEW status though.

Update reports of older versions
Take a look at old bug reports and try to reproduce them with the latest software version to find out whether the reports are still valid. If they have been fixed in the meantime, you can set their status to RESOLVED FIXED and add a comment in which version or on which Wikimedia website you could not reproduce the problem anymore. List of open reports that have not seen any changes in the last 18 months.

Update your own reports
Most of us have submitted bugs in the past and forgotten about them. Take a look at them and check whether they still apply in the latest software version. Go to the Query website and make sure that under "Status" UNCONFIRMED, NEW, ASSIGNED and REOPENED are checked. Under "Email and Numbering", enable "the reporter" and enter your email address below in the text field.

Further links
If you feel like going from triaging to writing code there are Annoying little bugs and Annoying large bugs available.