To prepare a Marshall speaker for use, you should do the following:

1. Unpack the speaker and check for any visible damage. If you notice any damage, do not use the speaker and contact the manufacturer for assistance.
2. If the speaker was shipped with a protective cover, remove the cover before using the speaker.
3. Make sure the speaker is placed on a stable and level surface.
4. Connect the speaker to a power source using the supplied power cord.
5. Connect your audio source to the speaker using a suitable audio cable.
6. Turn on the speaker and adjust the volume to a comfortable listening level.
7. If the speaker has any additional features, such as EQ controls or effects, you can adjust them to your liking.

That's it! You should now be able to enjoy your Marshall speaker.