Does the outline look good visually? Are there any larger interval jumps? Most singers and instrumentalists do not enjoy huge jumps in the music. To make it smoother, make sure a jump of a 7th goes to the next note up, the octave, that any intervals larger than a 5th are not used too often, and avoid jumps larger than an octave.
First «taste» test. Play the melody on your instrument. Get a feel for which notes want to go faster or slower, and if they like to be grouped together somewhere. Make any changes you like.
Now start jotting in the rhythm. Make faster notes 8th or 16th notes; longer notes quarter, half or whole. Keep it simple. Feel what notes you want more emphasized, this will give you an idea of what meter the piece wants to be in! Make any changes or adjustments.
What do you think the meter is? Do you feel the melody in 2, 3, 4 beats per measure or something else? Decide the time signature you want, and adjust the note values for all measures. Play through the melody and make any corrections you like.
Repeated rhythm patterns are nice. Try that!
Try not to be a perfectionist. This is your first try learning how to write a melody. The tune might even surprise you and get a «life» of its own!
Time to move on to how to add a chord sequence that fits with the melody>>>