There are some ways to make the kratom a bit more potent (and longer lasting). The methods i mention may not always work for anybody so it is best to experiment and see what works best for you

1) Mix the kratom with real (squeezed) grapefruit juice.
This can enhance the effects of the kratom (may make it work a bit better). Just squeeze a grapefruit (so you are sure you are using real grapefuit juice) and mix it with for instance 5 grams of powder. The grapefruit juice is bitter in itself but the taste and mix with kratom makes it actually better to drink.

2) Mix the kratom with chamomile tea (best for red strains)
The effects of chamomile tea and the kratom seem to enhance each other. Especially the relaxing effect of the chamomile tea. So this method is used best when you take kratom for sleep and relaxation.

3) Use kratom with Watercress vegetable
This can for instance be done with a blender. Mix the kratom powder with watercress leave and some choice fruit and make a smoothy. You can also just cook the watercress first and then mix it with the kratom. This can increase both the strenght of the kratom and also the duration.

4) Use kratom together with tumeric root powder (and a little bit of pepper)
I have not tried this myself but there are people claiming this really does increase both the duration of the kratom and the strenght of the effect.