Hi nvmybeauty - Welcome to the community and thank you for your question.
Just go the right side column in the community and find Community Calculators. Click on "Body Mass Index". Fill in your height and weight and have it calculate. It is your percentage of body fat! Now, take that number and post it in your weight tracker!
But please remember that a lot of them will give out different answes and won't be exact.
With all due respect, BMI is based on calculations and should be accurate from calculator to calculator. More information is provided in this post. http://www.medhelp.org/posts/Weight-Loss--Dieting/What-is-YOUR-BMI/show/977864