Latte art is not painted on top of a finished drink, it is created entirely through how milk is poured into espresso, which means the real skill being tested is milk steaming and pour control, not artistic drawing ability. If your milk is not textured correctly before you even start pouring, no pouring technique will save the pattern.
Properly steamed milk is the real foundation. You are aiming for microfoam, milk with extremely fine, barely visible bubbles rather than large, coarse foam, achieved by keeping the steam wand tip just below the milk's surface early in the process to introduce a controlled amount of air, then submerging it deeper to create a smooth whirlpool that refines the bubble size. Milk steamed to roughly 60 to 65 degrees Celsius, warm enough to be sweet-tasting but not scalded, is the general target, since overheated milk breaks down and loses the texture needed for art entirely.
The heart is the most common starting pattern for beginners, and for good reason, it forgives more error than the other patterns. You pour steamed milk from a height into the center of the espresso first to mix the base, then lower the pitcher close to the surface and pour a steady stream into roughly the same spot, letting the white circle grow, before pulling the pitcher up and through the middle in one motion to create the point at the bottom of the heart.
A rosetta, the fern-like leaf pattern, builds on the same fundamentals but adds a wiggling motion. After the same initial high pour to mix the base, you lower the pitcher and pour while gently rocking it side to side, which creates the layered leaf shapes, then finish by pulling straight back through the center to define the stem. It requires more consistent milk texture than a heart does, since any inconsistency in the microfoam shows up clearly across the wider pattern. Morgan Eckroth breaks the rosetta down on video, which is far more useful than a written description for this particular pattern.
A tulip is built from repeated hearts, essentially, you pour a small dollop, push the cup slightly, pour another slightly larger dollop on top of it, repeat a few times, then finish with a pull-through, stacking the shapes into layered petals. It is often considered the hardest of the three basic patterns to execute cleanly because timing between each dollop has to stay consistent.
The most common beginner mistakes are pouring too high for too long, which mixes the milk into the espresso without ever creating visible contrast on the surface, and moving the pitcher too fast or too slow relative to the milk flow, which distorts the pattern. Practicing with just water and dish soap, shaken to create foam, is a genuinely useful, low-cost way to practice pour control and pattern shape without wasting espresso and milk on every attempt.
None of this affects flavor, a poorly poured latte tastes identical to a beautifully poured one made from the same espresso and milk, so treat latte art as a fun skill to develop rather than a marker of whether a drink is actually good. If you want to see well-executed pours in person as a reference point, a specialty-leaning shop that steams its own milk to order, rather than using a pre-frothed dispenser, is where you are most likely to see it done well. Sprudge's introduction to latte art is a good primer on the vocabulary so you know what you are looking at.