The Rama writes that the strictures of the 9 days extend to until חצות on the 10th of Av. However, because this year the 10th of Av is Friday the din is a bit different.
The Mishna Berura writes that when the 10th of Av is Friday you are allowed to do these things earlier לכבוד שבת. There are 2 questions:
1. When does the heter start?
2. What exactly can you do?
The Shaarei teshuva and others write that washing clothes is permitted in the morning of the 10th when it is on Friday. It sounds like, the night of the 10th would be prohibited. However, many contemporary poskim are matir even on the night of the 10th. They explain as follows. When the acharonim wrote the morning of the 10th it was because in their day, these activities simply were not done (and could not be done) at night. Therefore, they wrote "morning", but really it is mutar from the night before.
The Poskim discuss what exactly is permitted. They point out that the acharonim (including the Mishna Berura) write that it is permitted to do these activities לכבוד שבת. Therefore, the only activities permitted are לכבוד שבת. In other words, you would not be permitted to wash weekday clothes Thursday night or Friday morning as that is not לכבוד שבת. Likewise, if you plan on taking a shower right before Shabbos (like most people do), it would be prohibited to shower on Thursday night because again, it is not being done לכבוד שבת.
There are acharonim who disagree and say that since these things are only prohibited מדין מנהג, the מנהג was never accepted on Erev Shabbos and therefore showering, doing laundry, etc. is permitted even not לכבוד שבת on Thursday night or Friday morning.
The contemporary poskim point out that there is no heter whatsoever to eat meat on Friday and there is no heter to listen to music or go swimming as these things are definately not לכבוד שבת and therefore according to everyone are prohibited.
As always ask your LOR any questions that are halacha l'maase.