Avoid the use of intense drying or heated appliances. As these can damage the hair shafts and make them more prone to splitting. Protect your hair from the sun so the use of a nice sun hat is also helpful. Try and manage your stress and also talk with your hairdresser as they can guide you with some good volume boosting products.
Lastly please make sure you are looking at your diet as well. Eat a well balanced diet. Whole foods everyday if you can. As a sudden drops in calories can have an impact of hair loss.
Be patient with a little love and love. you should be seeing a difference in about 3-6 months.