Create a new Adobe Illustrator Document with size: 2000 Height and 1500 Width, RGB color mode.
Take Rectangle Tool and draw a rectangle the size of your art board. Keep the rectangle selected and open Gradient Panel (Window, Gradient). Select Linear type gradient with Angle minus 90 degrees, change the color of the first gradient swatch to R=19, G=173, B=173 and the second gradient swatch to R=0, G=43, B=59.
Keep the gradient rectangle selected. Open Appearance Panel (Window, Appearance) then click on the little black arrow at the upper right part of the panel and select Add New Fill. Navigate to Swatch panel (Window, Swatches), select Patterns, Nature, Nature_ Foliage and from the Nature Foliage pattern swatches select Petals Three Color.
With this second fill selected, navigate to Transparency Panel (Window, Transparency) and change the blend mode to Soft Light.
We’ll add one more gradient in this step. Go to Appearance Panel, select Add New Fill, and this time choose Black to White Radial Gradient. Go to Transparency Panel to reduce Opacity to 60%.
Take Ellipse Tool and draw a circle while holding down Shift. Disable Stroke color and fill the circle with orange.
In this and next step we’ll create a star. With the orange circle selected, navigate to Effect, Distort and Transform, Pucker and Bloat, move the slider to -97%.
While the star shape is selected, go to Object, Expand Appearance to make the star shape editable.
While the star is selected, hold down Alt+Shift and take Selection Tool to resize the shape proportionally. Duplicate the star a few times, change the colors and Opacity of the duplicates. On the screenshot below is my example of a starry sky.
For your convenience I switched off the stars layer for awhile not to distract you.
Take Star Tool from the Tools panel, click on your art board to call the Star dialog box and enter 13 millimeters for Radius 1, 40 millimeters for Radius 2 and 8 for points. Choose yellow fill for the star, no stroke color.
Note: If your Units are not in millimeters, you can change them by going to Edit, Preferences, Units and Display performance, from the Stroke drop down menu choose Millimeters.
Duplicate the eight pointed star created in the previous step. While holding down Shift press up arrow key a few times to move the duplicate above the original. Use Direct Selection Tool (hold down Alt+Shift) to resize proportionally the duplicated star.
Select both eight pointed stars with Selection Tool, go to Object, Blend, Blend Options, from the Spacing drop down menu choose Specified Steps and enter 7. In order to apply the blend, go to Object, Blend, Make. See the result on the screenshot below.
Select the blended stars with selection tool, click on the bottom node in the middle and move the blended object downwards to increase the distance between the stars.
Click with Selection Tool on the blended object, hold down Alt key and move the object in right direction to duplicate it. Repeat this three more times until you get five vertical rows of stars on your art board. Select all rows with Selection Tool and go to Object, Expand and when the dialog box appears, click OK. Keep all stars selected and press Ctrl+G (Object, Group) to group them.
While the group of stars is still selected, go to Effect, Warp, from the fly out menu choose Shell Upper, check Horizontal option, set the Bend to 4% and Vertical Distortion to -8%. After applying the warp effect, go to Object, Expand Appearance.
Keep the stars group selected, navigate to Transparency panel, change the blend mode to Exclusion and lower Opacity to 10%.
Take Ellipse Tool and draw a yellow ellipse then in front of it draw another ellipse of any color. The second ellipse should be positioned so that a crescent shape of the yellow oval should be visible. See how I have placed them on the following screenshot.
Select both ovals with Selection Tool, navigate to Pathfinder panel and click on Minus Front button. The yellow moon crescent is ready.
Resize the previously created moon if necessary and position it at the upper right part of the image. If you like give the moon a slight white shade in the middle. For the purpose draw a thin crescent with Pen Tool (White Stroke Color) in the middle of the yellow moon crescent then apply Effect, Blur, Gaussian Blur, Radius 4-5 pixels. Reduce Opacity of the white crescent to about 20%.
Take Rectangle Tool and draw a rectangle covering approximately 1/3 of the art board. Fill with color R=0, G=27, B=46, no Stroke Color.
We’ll start creating buildings in this step. Take Rectangle Tool and start drawing rectangular shapes with Black Fill color. See my screenshot below for a reference.
Continue drawing rectangles with Rectangle Tool and Black Fill Color. As you can see on the screenshot, I have added also ellipses to make the buildings more varied.
Select all buildings using Selection Tool and press Ctrl+G to group them. While the group is selected, go to Effect, Stylize, Inner Glow, leave Blend Mode to Screen, select light yellow for color (R=246, G=255, B=156), set Opacity 30%, Blur: 2.47mm, check Edge.
Draw more buildings using Rectangle and Ellipse Tool, when ready, select all objects and press Ctrl+G to group them. Keep the group selected and go to Object, Arrange, Send Backward ( Ctrl+[ ) to move the new row of buildings before the previously created one.
Let us not leave the buildings dark. In this step we are going to add windows.
Grab Rectangle Tool and start drawing little yellow, white and pale blue rectangles. Reduce Opacity of some of them to give various shades.
Use also Ellipse and Rounded Rectangle Tool to add more windows.
Select all windows objects and group them (Ctrl+G).
Add windows to the back row of buildings too. Use again Rectangle and Rounded Rectangle Tool and play with Opacity option in Transparency panel. When ready, Group all back windows and move them backwards (Object, Arrange, Send Backward).
In order to hide the Inner Glow Effect at the down line of the buildings, draw in front a black rectangle using Rectangle Tool (Black Fill Color, no Stroke Color).
Now select all groups created in Step 18-25, i.e. both rows of buildings and the two windows groups. Press Ctrl+G to group them all. Duplicate the group and paste it in front (Ctrl+C, Ctrl+F). Navigate to Object, Transform, Reflect, check Horizontal. Move the reflected object so that its upper side to touch the bottom side of the original buildings. Send the reflected building backward (Ctrl+[) so that it is placed under the black rectangle created in Step 25.
See the screenshot below as a reference how your image should look like up to now.
While the reflected buildings group is selected, go to Object, Distort and Transform, Roughen, insert 4% for Size, 8/in for detail and press OK. Now you should have rippled buildings reflections.
As the reflections exceed the borders of the art board, in this step we are going to apply clipping mask.
Take Rectangle Tool and draw a rectangle (with any fill color) as you see on the screenshot below. When ready, take Selection Tool, select both the rectangle and the rippled reflections group, right mouse click and choose Make Clipping Mask.
Now your resulting image should resemble my screenshot below.
This is the final image. Hope you enjoyed this tut. Many thanks for reading it and good luck.