The main thing - don't put candles of different sizes and colors in each napkin, don't scatter five vases of flowers around, and don't try to combine every trending thing at once. That'll turn into chaos instead of a celebration. Also avoid dark tablecloths with dark flowers - it looks kind of gloomy, especially under artificial lighting.
Here's what actually works: pick one main color for accents and stick with it. Like, if you love pastels - soft green with white or cream flowers. If you prefer bold colors - deep burgundy or plum with gold details. A hack that most people miss: put a contrasting fabric under your main tablecloth or directly on the table, leaving 15-20 cm showing. You get this layered effect like in fancy decor, and it looks unexpectedly stunning and creates depth.
For candles - you don't need a bunch. Two or three matching candles in candleholders or in a glass, arranged diagonally across the table, do more for the atmosphere than a dozen different ones. For flowers, go with one arrangement in the middle or slightly to the side so it doesn't block people's faces. Low flowers in a low vase - that's 2026 in miniature, the trend actually works. Add simple place card holders or little cards with guests' names - it's a small thing, but it instantly makes the table feel more thoughtful and festive.