Continuous means perpetual, uninterrupted, without a break. I ran continuously for 30 minutes means that I ran every second of every minute for 30 minutes. I did not stop for a water break or to catch my breath or to walk for 5 steps. I just ran from beginning to end without stopping.
Continual means that it happens repeatedly, but there is a break in the action. I continually wash dishes all day means that I wash dishes repeatedly—-many times—-over the course of the day.
Try some sort of mnemonic device to help remember the difference between these two.
For example, continuous ends in -s, so you could associate it with the word stay or same or ceaseless, all words that start with the -s sound and describe the meaning of continuous.
Continual ends in -l, so you could associate it with the phrase leave and come back, which starts with an -l and describes the meaning of continual: an action that leaves and then comes back.
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