It’s important to keep your mats clean especially when you don’t use a towel over your mat.
I’ve used the advice of some of these sites.
Love to know- Their cleaning instructions are nice and detailed. I like using baking soda as an added ingredient to the soap. However, I read somewhere that using soap isn’t really good for your mat. 
Yoga Journal- I like their advice on using a big fluffy towel to dry off the mat instead of hanging it out straight.
I used to do an intensive cleaning of my mat every week. That didn’t help my mat since it got worn out fast. Good thing I met Monica of Dharma and Indigo Baby. She introduced to me her product, yoga mat spray. It’s awesome!
I personally use Dharma’s Yoga Mat Spray. I like the fact that’s it’s handy and all natural. You can keep it in your yoga bag and just spray on your mat before and after your practice. I don’t have to worry about harmful ingredients while I have my bare skin on the mat. After practice, I spray a more generous amount and wipe it off with my towel. This way the sweat and dirt doesn’t accumulate. I have the bigger bottle since I use this on the studio/shala mats too.
If you’re interested in buying a bottle for yourself, I sell SOLSTICE (lavender) and WINTER SOLSTICE (peppermint) Yoga Mat Spray (100ml) in my shala for P220.
Remember to keep your mats clean to have a healthy practice. 
Namaste.
-Karen