solidworks dimension tutorial for beginners
Open a new part document and create a sketch like below on the top plane (see the sketch tutorial)
Click on the smart dimension button in the sketch tab
Click on the upper horizontal line and drag the mouse upward to see the dimension. Click on the working area to inter the dimension then modify box appears. in this box you can modify the amount so for example we put 90mm. you have other options in this box, for example you can rebuild the model with you entered value or can mark the dimension to be appeared in the drawing file later.
Click ok or hit “inter” key to confirm the dimension. After that smart dimension command is still active and you can dimension all the lines or other entities one after another. When you click on a line or other elements to dimension them a properties window appers on the left on which you can add relations to the selected element too.