Well, fair enough if you never intend to use real instruments, but it's disappointing that you've decided to pick yourself up and carry on walking having stumbled across a brilliant opportunity to increase your knowledge and skills in using the orchestra.
If something sounds right, then it is 'done properly'. We can suggest repertoire examples and guidelines for treating any particular problem but after that it is the composer's choice how to proceed. Please eliminate, by extreme force if neccessary, any notion you may have that us 'classically trained' musicians have a Big Book of How to Do Things the Good Ol' Fashioned Right Way whose sacred and indisputable text we regard as law during acts of creation. You will be judged for not doing thing properly only if what you write sounds naff.
Please could this work ethic extend to spelling and grammar?