Also use this tip to greet "Hello All!" :)
For first tip, some lines of pseudo code to scale your sprite which instance of Image class while maintaining the aspect ratio.
//you have an instance of Image Image image = createInstanceOfImage(); //These lines will resize your sprite to half of screen's width while keeping the ratio image.width = .5f * Gdx.graphics.getWidth(); image.setScaling(Scaling.fillX); //To resize in height's scale image.width = .5f * Gdx.graphics.getHeight(); image.setScaling(Scaling.fillY);
If you can't figure out yet whether use width or height as scale, use Scaling.fill will help.