"Sweet Sixteen" is an epochal event in your life; the first of many one hopes you will enjoy so it really is a special trail marker along your road of life. Its importance is in your realization that you are to be the custodian of your own memories as well as the primary creator of them. You will have many more such epochal events to come: 18th and 21st birthdays; 30th, 40th, 50th, etc. as well; your wedding; the birth of your children, and so forth. It is good to see through your question that you are mature enough to realize the importance of these events as they unfold and that you already have a grasp on your role in striving for happiness as they unfold.
16, planning wise, is a manageable number to mark the event for future memory enhancement. Limit the number of people you invite to the sixteen people you most want to share it with. Have them sign a diary bound guest book so that in future years you can refer to it to see how you are still doing with them. Trust me, in some cases you will be startled to see how that works out over the long haul when you are thirty and beyond.
When you have settled on the site, make sure your 16 favorite colors are easily seen in the room and make sure a copious number of pictures will be taken during the event for you to keep and savor afterward.
Fashion tip: Put together an ensemble to wear that you really feel good about and retire it from your wardrobe after the event. Call it your Sweet 16 Ensemble. Photo the bejesus out of it and retire it for viewing at 30.
Take the time to make a playlist of your 16 favorite tunes with an eye towards hearing all of them at least once during your party.
THIS IS IMPORTANT! Make peace with your parents during the 16 days prior to the event. Remember that if this is to be a moment of joy for you, it will be a spasm of paranoia for your parents as they watch their little girl transform into the beginning steps of becoming a woman right before their eyes. Can you tell I am a Dad who has been there and done that with my own in the past? For Dad, it is the beginning of a heart tugging process as he watches his daughter start to slip away from him to the arms and affections of others. It is an unstated trauma to be suffered in silence by him especially if your joy is his highest priority. It will only get worse, of course, when you wed in later years. Please! Keep that thought in mind as you boogie your buns off at your sweet 16 party.
I wish you the best as you plan your event and I caution you to not set your bar of expectation too high as that could only lead to disappointment. Be realistic and steel your resolve to enjoy yourself no matter what happens with an attitude of gratitude. And, in the final analysis, do not be afraid to let the good times roll as you blow out the fire of your "Sixteen Candles" .
There is a story connected to that last line from my own past with my own daughter that constitutes one of our most treasured memories together. There were indeed 16 candles on her cake which she blew out after dancing with me to the tune of the same name. Midway through the dance, I handed her off to her boyfriend of the moment to finish the dance. He is long gone and easily forgotten. But, years later, that dance between the two of us is still often discussed as a treasured memory every time either of us hears the tune.
This answer has probably been more beneficial to me than it was to you but I hope you might have gotten an idea or two for your event from it. Hopefully, it will have been of benefit to us both. You go about the business of planning your own sweet 16. As for me, I think I will call my daughter.