Often the needs of succulents are misunderstood so it's a good thing you're here to learn the basics. And if you have any questions please get in touch!
Proper watering is by far the most important thing to master when caring for succulents.
Succulents and cacti are drought-tolerant plants, meaning they can go long periods without water as they store it inside their cells. However that does not mean you should water them sparingly! In nature succulents go long periods in drought then are drenched in heavy rains. You can reproduce this environment by watering your plants far less often than other houseplants; and when you do water them, ensure all of the soil gets drenched and drains away freely.
As a guide, in the summer I tend to water my succulents every two weeks and in the winter when lower temperatures mean soil does not dry as quickly I can wait as long as four to five weeks between waterings. Of course, this will vary a bit depending on the plant and your environment but it is wise to ensure the soil is completely dry before watering again. This can be tested using a moisture meter or by simply inserting a wooden skewer deep into the pot. If it comes out clean, you're okay to water again.
With succulents, when in doubt err on the side of underwatering, as succulents are prone to rot if they sit in damp soil for too long.
Soil or potting substrate
As mentioned above, when you water your succulents it is important to drench the soil and to let it drain quickly so that it is completely dry before watering again.
You can help this process along by ensuring you plant your succulents in a soil medium which is freely draining.
This can be as simple as amending regular potting mix with 50% perlite, which is cheap and easily available at most garden centres or big hardware stores with a garden section. More advanced succulent gardeners sometimes prefer to make a gritty mix that has very little organic material but if you ensure your potting medium gets totally dry between waterings this cheap and cheerful method will work just fine.
Sunlight is the last vital ingredient for raising healthy succulents. Many succulents, particularly Echeveria need a lot of sunlight to preserve their tightly packed rosette shape and intense colours. Place your succulents in bright windows (if you can't put them outside) and try to give them at least 6-8 hours of sunlight per day.
If you're introducing succulents to direct sunlight after a period of lower exposure, such as moving newly purchased succulents from a store to your home, make sure you do this in stages for a couple hours at a time before full exposure. Just like us, succulents can sunburn!