I recently got a juniper bonsai (my 9th one) from a garden center and its leaves were really pale.

I took it to a bonsai nursery and they told me it was overwatered because the soil was organic and didn't drain very fast.

It's been almost a week, and the leaves are still pale, but otherwise it seems healthy. The roots seemed fine as well.

What should I do?

JosephCooper wrote:

I recently got a juniper bonsai (my 9th one) from a garden center and its leaves were really pale.
It's been almost a week, and the leaves are still pale, but otherwise it seems healthy. The roots seemed fine as well.

Be patient. It's only been a week. Things are not growing at the moment so it may take till spring next year.
Or it's dead. Hard to tell without a picture.