Useful hack from one of the mechanics at my LBS. Lucozade sport bottles (the ones with the membrane across the drinking spout) are great for adding tubeless sealant to tyres. Pop sealant in the bottle, then push the spout over the valve (remove the core first). Squeeze the bottle, and the sealant goes into the tyre without dribbling down the outside of the valve. Pull the bottle off the valve, and the membrane stops any excess sealant sploshing all over the workshop.
Useful hack from one of the mechanics at my LBS. Lucozade sport bottles (the ones with the membrane across the drinking spout) are great for adding tubeless sealant to tyres. Pop sealant in the bottle, then push the spout over the valve (remove the core first). Squeeze the bottle, and the sealant goes into the tyre without dribbling down the outside of the valve. Pull the bottle off the valve, and the membrane stops any excess sealant sploshing all over the workshop.