Make sure to let the glue dry. Some years ago when I was living in Nigeria we had a young policeman stationed in our compound. I was riding my bike around the local roads, early in the morning only, too hot later and would occasionally get a flat from a wire or nail or something. One day I took a few tubes out to patch them. I had a good pump, and patch kit. I was under the thatched roof near the pool when the policeman came out to see.
Cooler and shady there. I started on the first one and he came closer. He politely asked if he could help. He showed me how he had been taught at the academy. Mark the spot, rough up the area, spread on the glue and WAIT. Like until the glue was really really dry. Then peel the back off the patch and apply. Then press it on really hard with a rounded object like the end of a screwdriver handle or similar. Talcum powder on the tube before reinstalling.
I was glad to have the lesson, I hadn’t been waiting long enough all those years. It was interesting that they taught tube patching at the police academy but if you were to get a flat somewhere it did make sense to be able to take care of it. Over the three years I lived there we had several pleasant patching sessions. I left just when he was taking his exams to be promoted. He passed and as we parted we wished each other well in our new endeavors. And thanks for the lessons.