However Syngonium are displayed, when it comes to light requirements they will do well in a position where they receive good light but no direct sunlight.
The soil needs to be evenly moist when you water, waiting for the soil to dry a little before evenly watering again. This means you should avoid the “little and often” approach, just remember to water well and then wait. Simple. In Winter the “wait” period will increase as the plant will take longer to dry out so adjust accordingly.
Humidity is some what important for Syngoniums because very dry air will encourage brown leaf crisping which on mass will distract from the beautiful leaves. All the usual ways of increasing humidity can be used to prevent this.
It’s good to try and feed an established plant a few times a month. Like most house plants Syngoniums do “rest” in Winter but for only a short period, so even in the middle of the coldest months outside (providing the indoor room is warm) it’s usual to see new leaves emerging. Therefore it’s fine to feed in Winter too if you want. But only if the plant is actually growing and therefore has need of the fertiliser. If in any doubt don’t bother.
This is one house plant which needs to be at the heart of your home because it demands warmth, even in cold months. An unheated conservatory in Winter for example is a no no. A minimum of 16°C / 61°F.