You should take protein and creatine as your key supplements or a Weight Gainer product if you want to gain maximum mass. Take a whey protein shake 2 to 3 times per day with one serving being just before your Halo immediately after training and take creatine monohydrate powder or a creatine tablet (like Creakic or Creadex). Start off taking 4 servings per day for the first 5 days and thereafter take 1 to 2 servings per day (2 on training days and 1 on non-training days). To gain mass at the fastest rate, you can either do the Nitro/Cell stack (Nitro 3 times per day and Cell-Tech twice on training days and once on non-training days - always take one serving of Nitro immediately, followed by Cell-Tech right after training) OR you can use a weight gainer like Mutant Mass (along with powdered creatine) or Mass-Tech or Muscle Fuel Anabolic (which already contain creatine). If your diet is good (high in calories and protein), go with the Nitro/Cell stack, if your diet isn't so good, go with one of the mass gainers - start off with 2 to 3 scoops twice daily and increase until you are gaining the desired amount of weight per week (1/2 to 2 kilos).
As with all supplements, please consult your physician first (especially if you have a medical condition). Do not use if you are pregnant/lactating or under the age of 18. Remember that an adequate state of hydration must be maintained when using this product. Have at least 8-12 large glasses of water per day. Taking more than the recommended dose will not improve results and may cause adverse reactions. For best results an appropriate muscle gain eating plan and training programme should be followed. High intakes of free-form amino acids may cause gastric discomfort in sensitive individuals - if this prolongs, reduce dosage or discontinue. Do not exceed the recommended daily intake. Nutritional supplements should not replace a varied diet. Keep out of the reach of young children.