How an e-learning course is designed is an important factor in how well the student pays attention and retains the information. Keeping your content simple and uncluttered is key to allowing your students to get the most out of every part of your online course.
Grab their attention from the beginning. 
From the very beginning, you want to grab your students’ attention. You can accomplish this by using texts, images and other visuals – it is important to make sure that they are attention-grabbing, as well as having relevance to the course content. Visually appealing content includes content that is uncluttered and creates a great introduction to the rest of the course.
Make it clear where the important information is.
When creating your content, you want to draw the students’ eye to the most important information on each slide. This can easily be done through font size, color and placement. Where you place your text is important; it should be arranged in a way that the students can easily go through the content and understand the main points.
It is better to remove information than have too much information. 
When you are done creating the course, it is best to go through and remove content rather than adding more. Adding more information can often times add clutter and reduces it’s effectiveness. All available free space does not need to be filled with information – the free space helps to draw the students attention towards the important information.
Students can only process a certain amount of information at a time, so bombarding them with information at every turn is not an effective teaching method. It is better to group the information with lists, bullet points, etc. Resist putting the information in as one giant clump of text, this reduces the likelihood of confusing the student.