re: please help me keep my new plants alive

Water in the morning. Avoid watering at night.

In my experience I've killed more plants by not watering them enough, overwatering my snake plants was the only time I've overwatered anything. I can tell when my potted plants have had enough water when the soil starts to drain out from the bottom of the plastic pot and the top of the soil doesn't look like a pool. That still varies by plant, but the plants I have love water regularly.

Based on what I'm reading from the plants you added, you'll want to water regularly. Some issues plants might face are establishing a good root system. I'd say water every other day for now as temperatures are rising. Other plant experts may tell you otherwise. I've had pretty good luck so far with what I've done for my plants.