Surprising someone is not easy! You have to go behind their back to do sneaky things; It might be talking to their friends without them knowing or their family.
You might even need to sneak into their house to do something.
It could also be as simple as getting them a surprise birthday present; Whatever it may be it is sneaky. I tried to surprise my friend by having an Heating and A/C system put into their home; They are low on money and cannot afford things like this. This was a legitimately hard process. I had to set up an appointment with an Heating and A/C specialist! He had to come to the home to do measurements and size up the house. He needed an appropriate measurement for the house to know what size Heating and A/C system my friend would be needing. This is substantial so that the Heating and A/C component does not have to labor as hard. I wanted to get my friend a ductless mini-split system. This was the easiest because I would not have to install ducts into her house. That would mean breaking apart some walls and putting the ducts in. It was all too much. The ductless mini-split also gave her several benefits… She could have zone control where different areas of the house could be different uneven temperatures. This would benefit her in the long run by adding years of life to her system. This is because the system would not have to labor as hard. I am cheerful to say that the surprise was successful and she had no idea until she walked in and saw the system.