I know you are going to hate me for this but. . . .
practice, practice, practice.
work from a good quality photo.
put it on your PC and zoom in when you need to work on detail.
It's all about hand / eye / brain co-ordination.
Like juggling the first time you try it you drop the balls.
but with practice you get more fluid and drop them less often.
Same with drawing.
the more you do it the better your hand / eye co-ordination gets and so the better you get at putting accurately
on paper what you see with your eyes.
Work the drawing up with very light strokes.
start with simple shapes to get a rough shape of what you are drawing
then go back and add more detail and refine the shape.
As the image develops you decide on what you want to focus on and bring out in the picture.