If you need to get a perfectly level line without using a traditional level, there are several methods you can use. One approach is to use a carpenter's square or other straightedge tool that has been marked with a measurement system in order to gauge the angle of the line. Alternatively, if you have two points that should be at exactly the same height, such as for installing cabinetry or wall moulding, try using an adjustable triangle made from metal or plastic and place it up against one point then measure down from its edge until it lines up with the second point. You can also create your own makeshift bubble level by filling an empty glass container (such as a drinking glass) halfway full of water and placing it on top of the surface where you want your line drawn; adjust until all air bubbles have disappeared beneath the surface of the water. Finally, if all else fails consider using string stretched tautly between two fixed points—the string will indicate whether any slant exists in between them so that adjustments can be made accordingly!