The last is the most important, a lot of people do this and that's the reason why they get into a lot of trouble, some might develop suicidal tendencies because of this. Gambling with funds that doesn't belong to you is going to put you in a precarious situation that maybe difficult to get out of. Don't get too confident in your strategies and think you can pull off something smart by borrowing money from others and trying to double it
I had an experience where we friend saw a game and stated that the game is very sure because someone assured them that they got information about the game and so they were certain that the game was going to turn out a win and so he got so much assurance and was tempted to go and borrow money to play the game but I discouraged that and so he decided to reduce the stake he wanted to stake and used a smaller amount eventually he won the game and wanted to regret it but again I reminded him that he should think about the chances that it was a loss what would have happened and after thinking of it he agreed that it was not a good idea to borrow and bet.