You can:
- Select them in the Layers list.
- Click on them with the Move tool (if in Pick a layer or guide mode, and with Preferences > Tool options > Move tool: Set layer or path as active, that are both defaults IIRC)
- Use the Layer ➤ Stack ➤ Select * entries
- Use the [PgUp],[PgDn],[Home],[End] keys (shortcuts for the above)