Baseline, just play some warmers with any experienced roper, ask them to give you some examples, and you will pick it up fast enough.
But in the end you wanna do what you feel most comfortable with, don't feel pressured into learning "fingerroll" or other styles if you are not comfortable with them, but then if that's what you wanna do then do it.
Here's the inevitable part, it mostly comes down to practise...
On the other hand, do you have 3-key lock? That is when you have up-right or up-left both held down and try pressing space, while at the same time, down+left or down+right may work, maybe you are hitting the roof constantly because you are not letting go of up or direction fast enough to miss the 3-key lock, if this is the case you can always find a keyboard with better sensitivity/reaction to your natural style, or, use a keychanger like me, my new keyboards spacebar is just horrible, so I remapped it to left control when I am roping, which works like a dream usually.
