You can easily sew a gym set. This costume is perfect for sports and everyday wear. This basic top is easy to pair with trousers, skirt and shorts.
This listing contains a 4 PDF files with pattern and tutorial.
The manual includes detailed step-by-step description with a lot of photos and recommendations. 
Patterns in 10 sizes, allowances included. Simply print them on paper, glue them together and follow the instructions to start sewing. The description is very detailed, so even a beginner can do it.
The instructions are as simple and clear as possible, without using professional terms, for your convenience.

For gym top you'll need:
Piece of knitted fabric:
Width 55" (140cm), length 27.5" (70cm).
Width 70.9" (180cm), length 27.5" (70cm).
Scissors 
Pencil
Pins
Threads
Needle
Pattern
Measuring tape
Sewing machine
PDF Reader
Printer
8 sheets of paper (A4 or Letter)
Ruler
Sealing tape
For biker shorts you'll need:
Piece of knitted fabric:
Width 55" (140cm), length 26.6" (67.5cm) for sizes 36-44,
length 57.5" (146cm) for size 46-54.
Width 70.9" (180cm), length 26.6" (67.5cm) for sizes 36-44,
length 30" (75cm) for size 46-54.
Elastic tape width: 1" (2.5cm),
length: 23.6"-25.6"-27.6"-29.5"-31.5"-33.5"-35.4"-37.4"-39.4"-41.3"
(60-65-70-75-80-85-90-95-100-105cm) for sizes 36-38-40-42-44-46-48-50-52-54. 
Scissors
Pencil
Pins
Threads
Pattern
Measuring tape
Safety pin
Sewing machine
PDF Reader
Printer
12 sheets of paper (A4 or Letter)
Ruler
Sealing tape

If you have any questions feel free to ask!

All designs and instructions are for personal use only, not for resale!