How can I clean up or restore an old acrylic painting?

The paintings were done by my grandmother in the 70s and 80s with acrylic paint. I'm familiar with oil paints but not acrylics and Ihave no idea how to safely remove the dust, mold, mildew and other dirt on the paintings. They're not worth anything financially, just sentimental. Any suggestions?How can I clean up or restore an old acrylic painting?
Do this at your own risk. I have cleaned many with a mild ammonia/soap solution then placed the painting in sunlight to bring back the colors especially the whites, about an hour. After, if there is some flaking, cracks, you can use a transparent glaze or gel then a varnish over top. All these bought at your local shop.How can I clean up or restore an old acrylic painting?
Very carefully. I've worked as an exhibit assistant at various art galleries and a museum, and my best advice is get a book on art conservation from the library. If that's not possible, look the topic up on Google and see what you can find. They will probably tell you, use a very soft CLEAN dry paint brush or cotton balls or Q-tips to remove as much surface dirt as slowly as you can. Then, they may suggest a gentle moist Q-tip cleaning. But the condition of the art needs to be assesed first. If the paint is flaking or chipped any where- DO NOT get it wet or clean the chipped area, as you may accidentally remove paint.