This is where making sure to have a good lawyer with experiences in these type of cases help,if you can't afford the lawyer the pd will help you. If this was me I would pray they can arrange a good plea to only one of the charges . Staying out of trouble,having a prior clean record and making sure to look presentable and respectful in court will help,your lawyer should have some type of game plan and be familiar with the da and judge.
Its important to discuss your plea options with your lawyer and maybe get a 2nd option if a conviction at trail is certain then a plea deal is gonna in your best interest. It's just a question of the best one that can arranged. The two selling charges are the ones to worry about and hope it be knocked down to one or both can be served at the time. If none of the offers are acceptable to you then once the trail comes and guilty verdict the sentence is gonna be higher.

