PLEASE NOTE: Alfred is currently in beta and as such, these help pages are currently being developed.
Every week, we'll add a few more tips on how to use some of the more advanced or hidden features in Alfred.
Simply use the hotkey combination you selected in the preferences which is Alt + Space by default.
If there's one app Alfred can't find but you don't want to rebuild your entire metadata index, go to the Spotlight Comment for that app, change anything (eg. add a comment) and save again. That will refresh the specific application's metadata, which should then start appearing in Alfred results again.
Want a few extra shortcuts? Here are a few ways you can speed things up:
You can modify these command hotkeys under the Results tab in the General preferences.