Cat Groomer As Needed

My cat Aria has a huge knot on her underside that we have been trying to brush out but since we do not own any sort of grooming supplies we don't want to risk accidentally cutting her if we use regular scissors. Her name is Aria and she is a longhair Calico who will be 2 in September. She is super lovey when she feels like it and can be timid around new people. She isn't the type to hiss, bite, or swat but can be temperamental at times. She does not have any special care needs. We know she does well with male cats and hates any and all dogs. She has not been around any other female cats so we don't know how she would react. There is public parking.