Since macro lenses are too expensive, a good alternative will be using an extension tube in between your camera body and your lens.
This tube extends the distance of your lens to the camera sensor.
Macro lens ~$700
extension tube ~$10
savings ~$690
But using extension tubes also bring challenges for a macro enthusiast.
You will lose light, and you need to shoot manually all the way. It is good to shoot on a sunny day to compensate the light lost.
Some of my Macro shots using a cheap extension tube and a 50mm F1.8 prime lens.
These are dragonflies who like to pose for the camera.
a closer look at dragonfly's eyes
peek a boo!!!
posing for a shot!