If it's clothing not showing up, as was mentioned earlier it's possibly a missing mesh. Make sure when you download items that you thoroughly read the post. The creator will always say if a mesh is needed and usually where to find it.

It might be a good idea for you to take some time and read this just to confirm you did everything correctly.

If you did, then this is probably your next step in looking for a solution.

It's always a good idea to take some time and learn how everything works. It sometimes seems confusing at first but it gets easier the more you know.

It's all L&P, however this is amusing and might give you an answer.

You might want to try here
http://www.simwardrobe.com/

It's the Fashion Show controller. Never used it, don't know anything about it, but you could take a look.