Hi there. It depends if you are just tinkering or wish to become structured about your approach. Drops will never give you a consistent result so without a scale, your current approach is just fine and great fun. We all begin like this and it is something not to cloud the issue with to make it too serious, too early, and risk dampening enthusiasm. Just record on paper exactly what you are doing each stage of the way. You will see that if you are mixing drops from each of three accords how quickly your maths will muddle because the formula will end up with fractions of drops and be unrepeatable.
If you wish to become more methodical, you might like to think about these things and continue playing with them in mind.
An accord is when two or more ingredients make a different smell to that of each of the blend, being neither one nor the other.
A scale is cheap enough at the jewellery end and will help you be accurate.
If you want to get into good methods then blend many versions with gradual increases of each ingredient to see where the balance is pleasant.
Here is what you have, but in what proportions?
Vial 1 = bergamot, oakmoss and labdanum
Vial 2 = rugosa rose, galbanum and rosewood
Vial 3 = jasmine, lemon, a couple drops of neroli and a few drops of vetiver
So if you are intending to blend those you will have this:-
Top notes:- Bergamot, Lemon, Neroli
Heart notes:- Rugosa Rose, Jasmine, Rosewood, Galbanum
Base notes:- Oakmoss, Labdanum, Vetiver
You can see now that this will be a fairly citrus, floral beginning with powdery green notes and a sharp edge to it. The proportions will be your key here. Galbanum is a terribly strong thing and will easily dominate, as is Labdanum. Think about which notes you would want to sing and which you may like to subdue or remove. There are many opinions on what proportions of top to base notes there are. A good place to start is 20/25/55 for ethanol and load the top more for oils.
I hope this helps you think about where you would like to go. I haven't smelled Cristalle so go to any net pages and look at what notes are in that perfume and read many descriptions and review of others. This will give you clues as to where to take yours next. Also look up the great chypres and learn what is in those.
Above all, just have fun. Also any blend you make will soften after leaving it a while so don't be too self critical too soon.