- Whatever choices make now always depend on earlier choices(and their
outcomes) we tend to use earlier knowledge to minimize bad and maximize good choices. [learnt choices]
- There are some choices which are in a sense "predetermined" like your interests and hobbies or choosing jazz over rock . [innate choices]
By nature humans(with no exception) are and always will be aligned towards achieving a more satisfying, more rewarding life.For some people rock is more satisfying and for some jazz is more satisfying.For some working for charity is more rewarding and for some making business is more rewarding.
These choices might depend on some predetermined configuration ( genetics, peers etc) or they can be purely random
Other choices like whether to take Job A or Job B will depend on you own interest in that job, the emoluments, the city you will be working in.You might choose Job A cause the emoluments are great. You might chose Job B cause your partner already lives in there.
So to answer
How to make a better choice?
Knowledge can help you make choices that are "good enough" but you cannot make better choices because you really don't know you candidates in absolute detail there is and always will be something that you might miss, foreseeing everything is not under human capability. You can make these (hypothetical) better choice only if you can see the whole future timeline (without affecting it) of all possible choices; funny enough now that you know everything there is no choice because now you are bound and would be selecting the best one only!
How to know your choice is the right one?
If you feel your beliefs are aligned with the choices, you are achieving something with the choices you made and you don't see any major harm on the way then you must be on the right track.
Are there any signs which can show that you are making the right choice?
Same as above, choice is an old issue in philosophy many ideas exists but in the end you just need to ask yourself.