In any sport there are teams that are at the top (favorites) and there are teams that are at the bottom (underdogs) of the success pyramid.
If we bet on favorites, we frequently will be right, but because many people will be placing the same bets, odds will be low. As a result, such bets will not be profitable.
If we bet on underdogs, odds will be high, but a frequency of correct bets will be low. As a result, such bets also will not be profitable.
The idea is to bet a fixed amount on a team that is underdog in view of majority, but will surprise many and shows a better result than it was in the past. Such strategy is called a fixed size betting. It is a low risk strategy that give some profit if the team will be chosen right. A fixed strategy is a strategy to bet on a particular fixed event, for example that a home (or away) team win/lose, for all games in a pre-selected group of games.
Let us consider an example.
Arsenal is a strong team. Majority of bettors believed that Arsenal had high chances to win in 2017-18 season, when it was an away team. This created a profitable opportunity for the fixed strategy to bet a fixed amount on home teams (underdogs) in all games, where Arsenal was the away team.

If we look into the table with games where Arsenal was an away team, we can see that betting on home teams in 2017-2018 season would give us over +108% return on all bets placed.
This strategy was profitable for three consecutive seasons.

If you want to increase your profit you should use the optimal strategies (see [1]).
In the next post we considered a simple way to start a micro business.
Reference
[1] Simple optimal betting, trading, investment strategies