The most visible difference between sounds in film and video is the EQ and compression that is used to make it sturdy. You can learn it by practicing and listening to sounds carefully. If you feel that it is not your cup of tea take help of sound mixer who is skilled and a professional to add clarity and boom to the sound. It is important to take care of the placement of microphone at every stage of recording. If you want the editing to go without hassles record the best sound during the shoot itself.
Taking care at the recording stage helps you in maintaining creativity and avoiding desperation at the editing stage. You can edit sound after locking the picture. It is good to split the tracks of the sound of the characters to minimize the distortion. Use sound editing programs to standardize the levels and for clean ups. Certain distortions which cannot be fixed should be substituted by looping, Foley and ADR. Foley is an art of adding sounds to actions that are subjective and unrealistic, like the sound of footsteps or crushing of paper. People who work on such sounds are known as Foley artists. You can practice recording tracks as a guide. You can even record the sound with one shooting camera and one without. This can cheat the camera and help you to sync the sound. Recording crystal clear sounds comes with practice and experience.
Real movies have good sound tracks that can be replaced either in parts or all together. When shooting, use creativity and make room for sound space for every scene, use sound effects, reverb and EQ to make that space. When editing sound digitally use compression carefully so that changes can be made easily. Using levels help to make the sound sturdier.