If you are flying offline you can choose your own difficulty/realism settings and enable icons on the map that show your position.
Otherwise, you need to get familiar with how compasses work in the sim (actually only the RAF ones are a bit funky to get used to initially) and plotting a course.
You can right click on the map and get plotting tools. Choosing the protractor you can measure angles. So, if you draw a line from your initial point to your desired next waypoint and then draw the second line to be vertical, you will get the true bearing to reach that waypoint.
Next, you need to adjust for magnetic deviation, which at that part of the globe in 1940 was a 10 degree offset.
Effectively, what this means is that if you want to fly a heading of 120 you should turn until your compass reads 130 (you just add 10 to the heading you want to fly).
Have a look at this excellent tutorial video by ATAG_Dutch:
http://www.youtube.com/watch?gl=US&f...&v=oyr9Ge8qN6Y