depends if u want to do it manually do it in photoshop,duplicate the layer so you have 2 layers.Now there will be a top layer & the bottom one put a blur the bottom layer then choose the top layer & erase the background leaving the subject in focus.
If u want natural bokeh u have to have a DSLR and it depends on the aperture you use the bigger the opening the more u'll have bokeh.Some lens have big aperture openings these lens are usually pricey.