Enter data using a userform

Hello,

My problem is i am trying to make a spreadsheet where data is entered using a userform. I am using 2 text boxes and 2 comboboxes, 2 buttons to add and one to close. I want it to be able on opening to find the first blank cell in column A, select it and insert the data in it and the respective cells to the right, save the data and be ready to insert more data on the next row until the user closes the userform. If anyone can suggest how to do this I would greatly appreciate their help or advice.