How fast you can raise your credit scores will depend on the reason why your credit scores aren't higher in the first place. If all three credit scores are low because of negative credit information, it's going to take time for that information to drop off of your credit reports. However, as the information gets older it loses negative value. If your credit scores are lower because you are in a lot of credit card debt and you pay it all off in one month, your credit scores could improve dramatically in a matter of days.
It is very important to identify the specific reasons why all three credit scores are not in a better shape before fixing them. Ordering all three credit reports and scores is often a necessary first step.