Here are some tips for you:
First, make sure what you are going to do, and show your ability to your boss, and if you have the related experience, you can try to let your boss understand that you need a higher salary. However, do not state it directly, for it may make your boss feel unhappy.
Second, after you show your ability and experience to your boss, you are wise to let your boss know that you can bring more profit to him directly or indirectly. That means you are worth a higher salary, and your boss will raise your salary himself or herself, because he knows that you are valuable for him or her, and the company can benefit more.
Third, remember: never push your boss to raise your salary by giving him or her pressure. Maybe, you can get a higher salary by doing this; however, it will harm your relationship with your boss. As soon as there is another person can do the job, too, you will find the axe in front of you.
Fourth, it is necessary to give your boss a hint that you want to have a higher salary. If you do not let him or her know, there will be no higher salary for you. You should make it known to the boss by skillful negotiations in a friendly way.
Fifth, the skillful negotiation needs your preparation ahead. Think of the points that give you favor, and try to find a better way to express it to your boss. Be well prepared for the negotiation, listing, brainstorming, organizing your ideas, etc. That is very important.
If you follow the tips, you are more likely to have a successful negotiation about your salary.