 Place a small portion of solvent ($$5$$-$$10 \: \text{mL}$$ for this chamber) into a TLC chamber with lid, along with a cut piece of filter paper. Dissolve liquid or solid samples (1 drop per $$\sim 1 \: \text{mL}$$ solvent) using a low boiling solvent (e.g. acetone or dichloromethane). Draw a pencil line on a TLC plate $$\sim 1 \: \text{cm}$$ from the bottom with a ruler, and mark the lanes. Don't put lanes too close to the edge or to each other. Spot a dilute sample on the pencil line of the correct lane, making very small spots ($$2 \: \text{mm}$$ in diameter). Rinse the spotter with a solvent (e.g. acetone) if going to use it for another sample. Place the sample in the TLC chamber with forceps, cap it, and leave it alone. Remove the plate when the solvent line is $$\sim 0.5 \: \text{cm}$$ from the top. Immediately mark the solvent line with a pencil. Visualize if necessary.