If interested, check out the Guidelines for Writers.
Payment is $10-$20 per article for articles of 250-500 words each.
If writing for this site, I encourage you to discuss the following clause with the site owner (especially the last sentence):
ALL WORK MUST BE ORIGINAL AND EXCLUSIVE TO FITMUSLIMAH.COM All rights and ownership will be transferred immediately to buyer (Fit Muslimah) upon payment. After payment, you must not use the articles in any way including as examples of your work.