WIFI antenna connection

I have had my board a few weeks now and everyday I try connect the antenna as yet Iv not managed, I have seen the video instruction, it looks so easy but I just cant do it so I use ethernet and an external USB adapter, anyone any tips? I think a good solution would be in purchase options to have already installed antennas … anyway Im new probably lacking a lot of skills but I just cant do it.. any help and or suggestions welcome