To add to tomtom and Eds points. The Ember and the tinder bundle are separate things. You need to establish your ember and then after its all nice and glowing put that ember in the tinder bundle, then you need to introduce lots of oxygen to it which is usually by blowing and waving it about (waving it about helps to keep down the moisture in it)
For your ember place something under your hearth or board to allow the ember to pile up, as this gets hotter it will coagulate into a lump. This needs to be on something stiff so that you do not break the structure of the ember when you move it. Remember, there is no rush, you can take a rest in between creating your ember and putting it in the tinder bundle.
A few of pics for you.
This one shows you the hearth or board, the ember that has been collected on the thin bit of wood under the board (directly under the notch) the bow and the spindle. There is no hurry to get the ember into the tinder bundle. Sometimes it is best though to lift the ember, on whatever it has collected, above the ground as it can get damp.
The ember is now in the tinder bundle (which should be as dry as possible) and it is being blown to life. Remember that you transfer moisture to the tinder bundle from your breath so wave it in the air quite frequently to help keep it dry.
This one shows body position, the arm locked against the leg for stability; excellent downward pressure can be attained this way, although not too hard! The foot is holding everything in place. The whole thing at this stage is getting the stability, correct pressure and your technique to come together so you can produce the ember, once you can do it you can start experimenting with other woods etc.
Friction firelighting is one of the skills that are much easier to be shown how to master than try to pick up by yourself, but, with perseverance you will be able to do it. Just keep at it!