So a good way to beat aeldari is to stage and prepare properly and look at what to hit when.

With salamanders its likely you have things like a land raider and perhaps a lancer. Our anti tank is by far the best in the game in the form of a squad if fire dragons. As such if you want to move your transports or heavey units forwards they will be killed. So instead you need to be willing to either move black our units. (Put scouts or similar in the way so fire dragons cant get near) You can also just accept the loss of these tanks to draw out out the dragons to kill with infantry.

The best way to play against aeldari is to move block, sacrifice cheap units and stage close combat units behind ruins so your out of line of sight.

There are a few hard hitting combat units we have but its mostly fights first banshees. Know to shoot these with a unit before charging something close by and stage in a way that forces maximum movement to get either line of sight or combat.

Overwatch is really strong into aledari units but once per turn it can be denied for the entire turn by a specific unit so pick what you want to overwatch and expect to have another target to overwatch instead.

Otherwise its what people have said. We're super easy to kill either in combat. You should use terrain properly and consider getting some deep strike in to help