Always take things you can wear more than once. No one will notice since you aren't at home. Also, don't be afraid to get things you need when you arrive.
Think about bring clothes that can be worn more than once that that you can repourpose with a change in accessories. Try rolling your clothes to create more space in your suitcase.
to maximize space, roll rather then fold clothes. Choose clothes that easily go from a day to night look. Take only 2 pair of shoes, one day and one night.