Technique: Edges Only Filter, Clone Brush
Edges Only Filter: This is a filter which gives you a sketch like effect. From experience I will tell you that it works best if the background is plain. For this one, I cloned brushed out the other plants that were around this sunflower. Then I clicked on Correct and then Filter Effects. From the list I chose, Edges Only . Then I selected a dark brown (you can use any color). I used an Edge Sensitivity of 130. The higher the sensitivity, the more detail you will get.
Clone Brush: This is a great tool for getting rid of stuff from a photo. In this case I wanted to get rid of the other sunflowers so I could showcase this one. You can find a full tutorial on the clone brush here.
Font is French Script. Paper and frame are by Angela Sharrow - the paper from Sunset Senerade and the frame from Timeless Vintage, both at SOTB