This has probably already happened to the Earth.
It is generally believed that the moon was formed from an impact event between a very young earth and a planet around the same size as Mars. In point of fact, it has been postulated that the young moon was responsible for the creation of life on earth, and that when it was newly formed from the debris ring around the earth, it was much closer to the earth, orbiting the earth every 6 hours or so and causing a massive tidal effect.
Ultimately, the closer you bring the moon to the Earth and the closer in relative size they are, the larger your tidal forces. The sun is also a factor though, so if you move the earth even slightly closer to the sun, and have a moon up close, you can end up with massive king tides as a result of alignment between sun and moon.
Mind you, the closer you put the Earth to the sun, the less time the earth will be in a habitable range (the sun is slowly heating up and in billions of years, Mars will actually be in the goldilocks zone, not earth) and having the moon closer, while potentially necessary for the establishment of life, may make the earth far less comfortable for the sustainment of life depending on what you're trying to achieve.
If the only thing you care about are tidal forces, then these configurations will help you. If you want this planet to harbour life to the point of intelligence, it may be a little more problematic. In any event, just move your moon closer to the earth and you get reasonable tidal variations quite quickly. You don't even have to move it much to have a great effect because of the squared effect of proximity on gravitational pull.
In other words, move it to half its current distance from the Earth, and your tidal forces quadruple. Move it to around a third of the current distance, and you have nearly 10 times the tidal forces in play. Of course, in both cases, your tides move much faster between high and low tides (unless you greatly slow down the rotation of the earth) so the impact on life is going to be greater than simple difference in tide height; you're generating a massive amount of momentum as well which brings its own problems that will have to be dealt with by life struggling to survive on the surface.