Honestly, your routine looks pretty wacky. That might work for a more advanced and enhanced bodybuilder who has very specific goals in mind, but for a natural novice, it is kinda useless. Judging from the height/weight you stated in your other question (180cm/66kg), your concern is primarily about gaining muscle, fat loss is not a primary issue. So we should look for a workout routine that is focused mainly on hypertrophy.
You should definitely be looking for a full body workout. The reason is that novices your age are able to fully recover within 48 hours from a workout with appropriate intensity (Practical Programming for Strength Training, p.30). Your body is not only able to recover from the exertion, he overcompensates, i.e. makes you stronger, so that in the future, you'll be able to handle the same intensity with more ease.
On the other hand, having an entire workout doing just biceps isolation work is detrimental to your goals. You are exposing your muscle to a stimulus he can't adequately recover and supercompensate from (yet), as illustraded in this picture:
Figuratively speaking, your body is too busy fixing the damage done by the workout to be able to adapt and gain strength. As a result, you might perform worse on your next biceps workout than before. Further, if you screw up your biceps on Saturday, you can expect to underperform on any pulling movements you do on Monday, thus further slowing down your overall gains.
So, bottom line, the question is "What is an adequate training?" This is a pretty difficult problem on which countless books and blogposts have been written. I think your best bet would be to stick with an established routine and modify it as little as possible in terms of excercise selection and volume. Because if you don't know exactly what you're doing, chances are, your changes will be detrimental to your goals.
One routine that comes to mind for your goals is Jason Blaha's Ice Cream Fitness. It's a 5x5 derivation with heavy emphasis on bodybuilding. The volume is quite impressive, but as a healthy 18 year old, you should be able to handle it with ease. You can execute all the barbell excercises with dumbbells instead for the next three months, but if you plan to stick with it for longer, you really need to buy a barbell or get a gym membership.
Some more general advice to help you get jacked:
- Eat a lot, especially a lot of protein (1.5g - 2g per kg bodyweight daily)! If you don't want to start counting calories and macros, you can just GOMAD (Gallon Of Milk A Day).
- Remember, muscles don't grow during exercise, they grow during rest after excercise. The 3-day-schedule of Ice Cream Fitness (or any other Starting Strength/Stronglifts clone) really is enough for novices. Resist the temptation to fill the days off with crap that possibly impedes your progress (HIIT, sprints, very long distance runs),...
- Sleep long and sleep good!
- Creatine monohydrate is a good investment. Protein poweder only for convenience reasons if you don't manage to get your daily macros with 'normal' food. Most other supplements' positive effects on training are highly disputed.
- Depending on how ripped you need to get and how much you are willing to put at risk for that goal, you might want to look into steroids. But going down this road can seriously and permanently fuck up your life if you have no clue of what you're doing and just follow the advice of some random gym rat or internet stranger. Go see a doctor with expertise in that field!
- Don't be a leg day skipper! Your amount of leg work in your suggested routine is ridiculously low. No, cycling and running does not substitute leg excercise! First, it is suggested that leg training increases testosterone levels and thus helps building upper muscles as well (although there is no strong scientific evidence to back that claim up). Second, if you neglect leg training, you WILL get to a point where you look into the mirror and realize you look like a dork with those big arms and chicken legs. So, unless you look like Robert Förstemann thanks to cycling or running alone, let me repeat: Don't be a leg day skipper!
