laundry day

It sounds like you haven't added any laundry equipment to your lot yet. I believe you need at least one washer, dryer, laundry tub, clothesline, or laundry hamper to get dirty clothes. 

Yes, it's very hard to do the laundry when there is nothing to wash them in. I love this pack.

It is one of my favourites, and I have a Laundry sim in my household :D .

First you need a hamper, when it's full enough it will allow you to search pockets, and than do the laundry.  you have either a tub or washer in the game. so choose where the laundry goes.  You can also add additives, I believe for a washer you need to upgrade it to have additives tray , you can just add them to the tub.

You can use flowers or food, which your sim has in the inventory. 

After you added laundry to your washer, and additives, you click it again and you can wash it. 

In the tub it takes long time and give them quite a workout :) 

in the washer your sim can even watch the laundry. 

Now you need either clothes line or a dryer. After the wash is done, you can either hang it or add it to the dryer. Make sure you will clin the lint tray from the dryer after each cycle, so you'll avoid some fires ( talking from experience) . when its done drying you can put the laundry away.

One tip, I use 2 hampers for my families, cause they fill up quickly, 

I put a hamper in each bathroom. Believe it or not, the dirty laundry does end up in the hampers. Have fun!