You have some options.
1. You can make a macro and attach it to a command button so that a user can use the Ctrl key to make multiple selctions of items in a single column, or entire rows but it must be one or the other, not a combination. When the user has completed their selection, they can click the button and activate the macro to execute the copy action.
2. You can use an worksheet event macro which will activate dependent upon which type event you choose, to execute the copy as the user makes changes to a cell or moves from one cell to another, or goes to a different worksheet. But again, it must be one type of event and not a combination.
There are numerous approaches to doing what you want. But you must first decide in your own mind how you want the user to be able to activate the macro and at what point you want the copy transaction to occur. You need to be clear about what the user is selecting, eg. a cell, a row, a column and which rows and columns by letter or number, rather than header title. The original post contains most of the necessar information to formulate a macro, but it is unclear how you expect the user to make the selection and when the copy transaction is to occur.
Here is a Worksheet_SelectionChange procedure that will activate based on selection changes on the worksheet.
Code:
Private Sub Worksheet_SelectionChange(ByVal Target As Range)
If Target.Columns.Count > 1 Then Exit Sub
Application.EnableEvents = False
If Sheets("Summary").Range("B12") = "" Then
Range("A" & Target.Row).Resize(1, 4).Copy Sheets("Summary").Range("B12")
Else
Range("A" & Target.Row).Resize(1, 4).Copy Sheets("Summary").Cells(Rows.Count, 2).End(xlUp)(2)
End If
Application.EnableEvents = True
End Sub
This automatically runs as the user makes selections. To install the code, right click the name tab of the sheet where the user will make selections. Click 'View Code' in the pop up mehnu, then copy and paste the code into the code window of the vbEditor. Close the vbEditor and save your workbook as a macro enabled workbook to preserve the code. The code will now execute for any selection change on the worksheet. To prevent the code from running, Click Developer on the ribbon, then click the design mode icon, (Triangle and ruler).