In the Modeling view click the New experiment button. Name the experiment and click Create. Remember to use a good naming strategy for your versions. Version 1, Version 2, Version 3 etc., becomes a little hard to decipher after a while.
If a block has not been selected on the canvas the new block will appear at the bottom of the model. Drag the block to where you want it in the model. Connect the new block to another block by using hold-and-drag between the connecting points.
Select an unconnected block on the canvas and then select the new block that you want to add in the right section. The new block will appear under the previous block on the canvas. A connection between the two blocks is created automatically.
Make sure the newly added block is selected. In the parameter section in the Inspector set the parameters for the block. The Information pop-up will give you information on which setting you need to set.
If needed, remove a connector or block by selecting it and then pushing the delete or backward key on the keyboard or clicking the Delete selection button in the GUI.