Eating less is easy just don't put it in your mouth
What is your average weight loss each week? two to three pounds is really good so if you're around that rate worry not.
If you want to maximise your loss you have to be scientific. You need to sign up to a food logging website, there are lots of them out there that are free. You enter the food you've eaten and it tells you the calories, fats, carbs and protein etc. They can help show you just what you are eating and in what values
When was your last appointment with your dietitian? what advice did they give you about calories and protein intake? You need to make sure you're getting at least 70g of protein per day and 60% of your food should be protein based 30% carbs and 15% fats. Aim to get at least 900 to 1000 calories a day, more if you are exercising
Often you will find increasing your protein intake actually speeds up weight loss so that might be the answer. If you are making bad food choices or not eating enough then that might be the reason for your slow loss. You also need to make sure you drink lots of fluid
Exercise is vital if you want to maximise your weight loss. Walking is pretty rubbish to be honest in terms of the amount of calories burnt over the time it takes to do them, and even walking quickly for 30 minutes will burn just over 200 calories. Think about it if a pound of fat is worth about 3500 calories so walking for 30 minutes a day would take you 17 days to burn up one pound, hardly earth shattering
Do you know anyone with an exercise bike they no longer use or maybe even some workout DVDs that they don't want? as these would help you to lose weight quicker than just walking a little each day
Good luck with it